Re: tracking down why a module was loaded?;

[ed]

Gunther Birznieks wrote:

> I unfortunately have to agree.
> 

> And in the end, the salaries for mod_perl programmers
> are pretty high right now because of it -- so will a system really cost
> less to develop in mod_perl than in Java if Java programmers are becoming
> less expensive than mod_perl programmers?
> 

Mod_perl programmers are more expensive as individuals,
because mod_perl is more powerful, and allows you access
to the Apache API; mod_perlers are more saavy.
One or two mod_perlers could do the
work of a java shop of ten in half the time. Still a savings.
Not to mention the hardware that goes with Java by fiat!

ed

Re: [OT] advice needed.

[ed]

Mike,

I think many developers share a similar desire to not
have projects (that leverage free software) close down
what are really generic programming techniques,
routines, classes, protocols, etc.  And further,
we'd like to contribute enhancements and documentation
based upon our work.

I'd like to find a lawyer who has experience and/or
want to pursue legal means of removing the friction
that keeps us from giving back. Part of that work would
of course involve contract writing/editing. I'm hiring.
Contact me if you are such.

It is up to you to educate your potential employers
about just how much of what you do is pior open
art and how free software can empower them.
That means the first contract has to be amended.
;-)

Be very explicit about your intentions from the get go,
and repeat yourself a few times; never assume they'll
look at the code or even closely read your written
self-description.

Ed

Michael Dearman wrote:

> Where the heck does trying to do the right thing by
> GPL (or similar), in attempting to return some improved
> OpenSource code to the community. Or however the license
> phrases it. Shouldn't these contracts address that issue
> specifically, especially when the project is _based_ on
> OpenSource/GPL'd code?
>
> Mike D.

Re: Determining when a cached item is out of date

[Ed]

On Thu, Jan 16, 2003 at 06:33:52PM +0100, Honza Pazdziora wrote:
> On Thu, Jan 16, 2003 at 06:05:30AM -0600, Christopher L. Everett wrote:
> > 
> > Do AxKit and PageKit pay such close attention to caching because XML
> > processing is so deadly slow that one doesn't have a hope of reasonable
> > response times on a fast but lightly loaded server otherwise?  Or is
> > it because even a fast server would quickly be on its knees under
> > anything more than a light load?
> 
> It really pays off to do any steps that will increase the throughput.
> And AxKit is well suited for caching because it has clear layers and
> interfaces between them. So I see AxKit doing caching not only to get
> the performance, but also "just because it can". You cannot do the
> caching easily with more dirty approaches.
> 
> > With a MVC type architecture, would it make sense to have the Model
> > objects maintain the XML related to the content I want to serve as
> > static files so that a simple stat of the appropriate XML file tells
> > me if my cached HTML document is out of date?
> 
> Well, AxKit uses filesystem cache, doesn't it?
> 
> It really depends on how much precission you need to achieve. If you
> run a website that lists cinema programs, it's just fine that your
> public will see the updated pages after five minutes, not immediatelly
> after they were changed by the data manager. Then you can really go
> with simply timing out the items in the cache.
> 
> If you need to do something more real-time, you might prefer the push
> approach of MVC (because pull involves too much processing anyway, as
> you have said), and then you have a small problem with MySQL. As it
> lacks trigger support, you will have to send the push invalidation
> from you applications. Which might or might not be a problem, it
> depends on how many of them you have.

I have pages that update as often as 15 seconds.  I just use mtime() and
has_changed() properly in my custom provider Provider.pm's or rely on
the File::Provider's checking the stat of the xml files.  Mostly users are
getting cached files.

For xsp's that are no_cache(1), the code that generates the inforation that
gets sent throught the taglib does its own caching.  Just as if it were a
plain mod_perl handler.  they use IPC::MM and Cache::Cache (usually filecache)

I've fooled w/ having the cache use different databases but finally decided it
didn't make much of a difference since the os and disk can be tuned effectively.
The standard rules apply: put the cache on its own disk spindle, ie. not on 
the same physical disk as your sql database etc.  Makes a big difference ...
you can see w/ vmstat, systat etc.

The only trouble is cleaning up the ever growing stale cache.  So, I use this
simple script in my /etc/daily.local file, or a guy could use cron.

Its similar to what's openbsd uses for its cleaning of /tmp,/var/tmp in the
/etc/daily script.

Ed.

# cat /etc/clean_www.conf
CLEAN_WWW_DIRS="/u4/www/cache /var/www/temp"

# cat /usr/local/sbin/clean_www
#!/bin/sh -
# $Id: clean_www.sh,v 1.2 2003/01/03 00:18:27 entropic Exp $

: ${CLEAN_WWW_CONF:=/etc/clean_www.conf}

clean_dir() {
dir=$1
echo "Removing scratch and junk files from '$dir':"
if [ -d $dir -a ! -L $dir ]; then
cd $dir && {
find . ! -name . -atime +1 -execdir rm -f -- {} \;
find . ! -name . -type d -mtime +1 -execdir rmdir -- {} \; \
>/dev/null 2>&1; }
fi
}

if [ -f $CLEAN_WWW_CONF ]; then
. $CLEAN_WWW_CONF
fi

if [ "X${CLEAN_WWW_CONF}" != X"" ]; then
echo ""
for cfg_dir in $CLEAN_WWW_DIRS; do
clean_dir "${cfg_dir}";
done
fi

Re: [error] Can't locate CGI.pm in @INC

[Ed]

On Wed, May 28, 2003 at 09:11:06PM -0700, Brown, Jeffrey wrote:
> Here are the results from the log file:
> 
> [Wed May 28 20:50:21 2003] [error] No such file or directory at
> /htdocs/perl/first.pl line 6 during global destruction.

openbsd's httpd is chrooted.

Ed.

Re: [error] Can't locate CGI.pm in @INC

[Ed]

On Thu, May 29, 2003 at 04:12:51PM +1000, Stas Bekman wrote:
> Brown, Jeffrey wrote:
> >Problem solved!
> >
> >You all are a fantastic resource to newbies!
> >
> >Jeff
> >
> >-Original Message-
> >From: Ed [mailto:[EMAIL PROTECTED] 
> >Sent: Wednesday, May 28, 2003 9:28 PM
> >To: Brown, Jeffrey; [EMAIL PROTECTED]
> >
> >On Wed, May 28, 2003 at 09:11:06PM -0700, Brown, Jeffrey wrote:
> >
> >>Here are the results from the log file:
> >>
> >>[Wed May 28 20:50:21 2003] [error] No such file or directory at
> >>/htdocs/perl/first.pl line 6 during global destruction.
> >
> >
> >openbsd's httpd is chrooted.
> 
> Again, can someone please post a patch/addition for the troubleshooting.pod 
> doc explaining the problem and the solution in details. I've seen this kind 
> of questions more than once here.
> 
> Should go into OpenBSD cat at:
> http://perl.apache.org/docs/1.0/guide/troubleshooting.html#OS_Specific_Notes
> Get the pod by clicking on the [src] button.

For the list archive:

- rtfm
"-u" disables chroot. httpd(8)
http://www.openbsd.org/faq/faq10.html#httpdchroot


- set up chroot basics
The doc for setting up an anoncvs mirror could be adapted for mod_perl.
http://www.openbsd.org/anoncvs.shar
Ofcourse much of it doesn't apply, but the part about ld.so, etc. is
helpful.


- List archives
dreamwvr figured out how to actually get things to work and posted notes
to the list. (so see archives)


- 3.3-current (soon to be 3.4)
And one last bit added after 3.3 was released, Revision 1.7 to apachectl:
http://www.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/httpd/src/support/apachectl

pick's up httpd_flags from /etc/rc.conf, so you can just add "-DSSL -u" to
httpd_flags.


- ports
The openbsd ports system is not by default configured to install
perl modules or packages in the chroot environment. You would have to
set PREFIX or LOCALBASE. see bsd.port.mk(5) and ports(7)
(PHP ports are set up for chroot installs).


- goolge
A nice HOWTO run mod_perl chrooted would be nice.  maybe someone's
already written it?


I hope this helps some.


Ed.

Re: proxy front to modperl back with 1.3.24

[Ed]

FYI,

There is a patch this morning from the mod_proxy maintainer.

http://marc.theaimsgroup.com/?l=apache-httpd-dev&m=101810478231242&w=2

Ed

On Fri, Apr 05, 2002 at 02:33:35PM -0800, ___cliff rayman___ wrote:
> i had trouble using a proxy front end to both
> a mod_perl and mod_php back end servers.
> 
> this works fine for me at 1.3.23, so I reverted
> back to it.  i copied the httpd.conf files
> from the 1.3.24 to my downgraded 1.3.23
> and everything worked correctly on the first
> try.
> 
> i was getting garbage characters before the first
>  or doctype tag, and a 0 character at
> the end.  also, there was a delay before the
> connection would close.  i tried turning keep
> alives off and on in the back end server,
> but i did not note a change in behavior
> i also tried some different buffer directives,
> including the new ProxyIOBufferSize.
> 
> these garbage characters and delays were
> not present serving static content from the
> front end server, or when directly requesting
> content directly from either of the back end
> servers.
> 
> i know they've made some mods to the
> proxy module, including support for HTTP/1.1,
> but i did not have time to research the exact
> cause of the problem.
> 
> just a word of warning before someone
> spends hours in frustration, or perhaps
> someone can give me a tip if they've
> solved this problem.
> 
> --
> ___cliff [EMAIL PROTECTED]http://www.genwax.com/
> 
> 

Re: [RFC] Dynamic image generator handler

[Ed]

On Fri, May 10, 2002 at 10:46:11AM -0700, Michael A Nachbaur wrote:
> On Fri, 10 May 2002 08:32:55 +0200
> Robert <[EMAIL PROTECTED]> wrote:
> 
> > Take a look at Apache::ImageMagick
> 
> In my benchmarks I ran, ImageMagick was way slower than GD.  I wrote a
> little test, rendering a little text image of 120x30.  With ImageMagick,
> I was getting 0.3 rps, and under GD with similar circumstances I was
> getting 1.5rps.  I'm sure I could've optimized the ImageMagick one a bit
> further, but that quick test settled it for me.
> 
> I looked at Apache::ImageMagick last night however, and although it
> seems pretty usefull, it doesn't really address what I want to do with
> my module.

I'm using Imlib2 w/ the c interface (http://freshmeat.net/projects/imlib2perl/)

I needed antialias lines, alpha's etc.  I modified my app to use a 'dbi' like
interface for potentially any media driver.  The diferent 'media drivers',
gd, imlib2, *pdf/*tex etc all have different ideas how to draw a line, circle,
polygon, text, add colors etc. Now all I have to do to use diffent libraries
such as Media->new(Driver => 'imlib2'), or Media->new(Driver => 'gd'),
Media->new(Driver => 'svg'), Media->new(Driver => 'pdflib') etc.

There are may libraries out there, gd, imlib, imlib2, libart, povray, gdk,
flash, pdfAPI2, pdflib, tex, latex, svg, imager, imagemagic, ...

There are may good reasons to be able to 'just drop in' a driver ... just
look at why the unified interface 'DBI' was developed for RDBM's .

Ed

Re: [RFC] Dynamic image generator handler

[Ed]

gt; leverage that, although I'm not certain how difficult it would be to
> interface with CSS files. As far as I know, there are Perl CSS parsers,
> but I have yet to use them. The configuration for a preset config
> template would be layered, so the earlier the definition, the lower the
> layer is. The real important part here, is the "name" attribute of any
> element, as this identifies where input can be indicated. The above
> preset could be used by invoking the following URI.


I used CSS.pm for a bit but it was too fat w/ Parse::RecDecent. To unify my
app and the browser I use axkit to 'generate' the css from an xml file.


 
black
geneva
arial
7px
white
 


.back {
color: black;
font-family: geneva, arial;
font-size: 7px;
background-color: white;
}

Creating complicated css files are difficult but my drawing app can load its
info from the uri, an xml file, a rdbm , Config::General, inifiles or whatever
and use different output methods such as axkit's providers to parse the 
'color config' to render the *.css file to the browser.

This way the document, style, skin and images are all unified.

Graphics::ColorNames works wonderfully to help handle all the different color
needs.

> 
>   http://localhost/genImage/preset=thumbnail-image;src=/images/ducks.jpg
> 
> As you can see, the preset is invoked by passing it's name as an
> attribute, and any element that has a name attribute, it's value can be
> provided on the URI. If an element has both a value and a name
> attribute, the value in the config file can be used as a default.
> 
> *) Caching Schemes
> 
> A caching scheme similar to AxKit could be used. The current module
> takes all the input arguments, sorts them (including all values that are
> not provided, for completeness), and takes it's MD5 checksum. That
> becomes the image's filename on the system. It is placed in a temporary
> directory, and any further requests to that same URI, the file is pulled
> from the filesystem without regenerating the image. Further, the code
> has been blatantly ripped off from AxKit, which separates the directory
> into two sub-levels, to prevent performance problems of having too many
> files in one directory.
> 
> Note: To prevent the filesystem from filling up, due to DoS attacks, it
> may be prudent to have a cron job periodically cull files that have the
> oldest access time.


Cache::Cache is appropriate here ... 



> 
> *) Image Manipulation Modules
> 
> My current code uses GD for text writing, and I'm quite happy with it.
> It is extremely fast, and creates nice text output when compiled with a
> TTF font engine. Looking forward however, it may not be as desirable if
> things like drop shadows is to be done. GD can work with multiple
> images, can resize them, etc, but the advanced features are still
> unknown.
> 
> *) File Expiration Headers and Browser Caching
> 
> With my current code, it seems that browsers are reluctant to cache
> these dynamically generated images. I have passed Expires: headers to
> tell the browser to cache file file for a long period of time (2+
> weeks), but I have been unsuccessful. I know the caching headers are
> complex, and needs more than one simple header, but fixing this has
> moved to the back-burner of my project. However, if more complicated
> processing is to be done, and with more images, it will be crucial to
> make browsers cache these images.


I create a digest w/ MD5 or SHA1 for the image/pdf and use it as the filename
and the Cache::Cache key.

The cache is easily invalidated if the source image file failes a -e test.
I also use cron to delete stale image files.

The generated now static image is redirected-to or referenced in the html.  
I found that it is important to complete the  processing of the images before 
the referencing html document gets served, ... rather than having the html 
document initiate dynamic imbeded links to create the image.  Letting apache 
serve images as static image-files has proved rock solid for me 
... (note keep-alives).  There is nothing worse than to pull a page and have
to wait for each of the images to show up.

Browsers, proxies and users are all real pains to deal w/ when the uri has
a query string.  Digest's are ugly but they play much better w/ everybody.

014d1c89fc3da6e15e0069000dfa381e44239af71021057594.png

Ed

Re: [Templates] Re: Separating Aspects (Re: separating C from V in MVC)

[Ed]

On Fri, Jun 07, 2002 at 09:14:25AM +0100, Tony Bowden wrote:
> On Thu, Jun 06, 2002 at 05:08:56PM -0400, Sam Tregar wrote:
> > > Suppose you have a model object for a concert which includes a date.  On
> > > one page, the designers want to dipslay the date in a verbose way with
> > > the month spelled out, but on another they want it abbreviated and fixed
> > > length so that dates line up nicely.  Would you put that formatting in
> > > the controller?
> > In the script:
> > 
> >$template->param(long_date  => $long_date,
> > short_date => $short_date);
> > In the template:
> > 
> >The long date:   
> >The short date: 
> 
> Can I vote for "yick" on this?
> 
> A designer should never have to come to a programmer just to change the
> formatting of a date.
> 
> I'm a huge fan of passing Date::Simple objects, which can then take a
> strftime format string:
> 
>   [% date.format("%d %b %y") %]
>   [% date.format("%Y-%m-%d") %]
> 
> Tony
> 

xmlns:date="http://exslt.org/dates-and-times";  wins for me.

date:date-time()
date:date()
date:time()
date:month-name()
... etc

xslt solutions win for me because it its supported (or seems to be)
by many major languages, and applications. 

xslt stylesheets can be processed, reused and shared with my c,perl,
java,javascript, ruby, mozilla, ieexplorer ... kde apps, gnome apps
... etc

Imagine having your templates and data supported and interoperable ...

Aren't we trying to rid the world of proprietary (only works here) things?

Ed   (an axkit lover)

Re: E-commerce payment systems for apache/mod_perl

[Ed]

On Tue, Jul 02, 2002 at 10:43:14PM -0500, David Dyer-Bennet wrote:
> Any obvious choices for a relatively small-scale e-commerce payment
> processing system for a server running apache / mod_perl?  

http://interchange.redhat.com/
- it's mature
- we wrote our own but i'd use it instead if I had to start over
http://www.ipaymentinc.com/
- reseller for authorize.net
http://authorize.net/
- big transaction provider
- supported cpan module (simple/trivial)
http://www.dhl.com/
- we get really cheap rates for dhl's next day shipping service world wide
  (1-2 days continential us @ $6)
  (3-4 days door2door to pakistan from indianapolis @ $21)
  ... much, much cheaper than even the cheapest ups-residential-ground
- ups has well developed xml API's, dhl dosn't

Ed

Re: Apache Hello World Benchmarks Updated

[Ed]

Hi,

(as far as i can tell after a quick peek at the code and some debugging)

It looks like there is a bug w/ AxKit::run_axkit_engine() and/or
Apache::AxKit::Cache::_get_stats()

run_axkit_engine() wants to create a .gzip cachefile when AxGzipOutput is off.

When AxGzipOutput is off the .gzip file is never made and _get_stats() 
returns w/ !$self->{file_exists} effectivly disabling delivering cached copies.

With AxGzipOutput enabled both files are created and appropriate cached copies
are delivered as expected.

I haven't decided for myself a best fix except for just enabling AxGzipOutput.

So, I reran hello/bench.pl w/ AxGzipOutput On and sped axkit up quite a bit.

attached are some diffs and a couple of 1 sec bench.pl runs.  Would be
interesting to see how axkit compares now?

Thanks,

Ed

On Mon, Oct 14, 2002 at 12:26:06AM -0700, Josh Chamas wrote:
> Hey,
> 
> The Apache Hello World benchmarks are updated at
> 
>   http://chamas.com/bench/
> 
> The changes that affect performance numbers include:
> 
>   Set MaxRequestsPerChild to 1000 globally for more realistic run.
> 
>   Set MaxRequestsPerChild to 100 for applications that seem to leak
>   memory which include Embperl 2.0, HTML::Mason, and Template Toolkit.
>   This is a more typical setting in a mod_perl type application that
>   leaks memory, so should be fairly representative benchmark setting.
> 
> Note that the latter change seemed to have the most benefit for Embperl 2.0,
> with some benefit for Template Toolkit & less ( but some ) for HTML::Mason
> on the memory usage numbers.
> 
> Regards,
> 
> Josh
> 
> Josh Chamas, Founder   phone:925-552-0128
> Chamas Enterprises Inc.http://www.chamas.com
> NodeWorks Link Checkinghttp://www.nodeworks.com
> 


--- hello/bench.pl  Sun Oct 13 04:07:35 2002
+++ hello-gz/bench.pl   Tue Oct 15 00:15:48 2002
@@ -106,7 +106,7 @@
 
 # FIND AB
 my $httpd_dir = $HTTPD_DIR;
-$AB = "$httpd_dir/ab";
+$AB = '/usr/sbin/ab'; #"$httpd_dir/ab";
 unless(-x $AB) {
 print "ab benchmark utility not found at $AB, using 'ab' in PATH\n";
 $AB = 'ab';


--- hello/bench.pl  Sun Oct 13 04:07:35 2002
+++ hello-gz/bench-gz.plTue Oct 15 00:16:32 2002
@@ -106,7 +106,7 @@
 
 # FIND AB
 my $httpd_dir = $HTTPD_DIR;
-$AB = "$httpd_dir/ab";
+$AB = '/usr/sbin/ab'; #"$httpd_dir/ab";
 unless(-x $AB) {
 print "ab benchmark utility not found at $AB, using 'ab' in PATH\n";
 $AB = 'ab';
@@ -583,6 +583,7 @@
AxAddStyleMap application/x-xpathscript 
+Apache::AxKit::Language::XPathScript
   AxAddProcessor text/xsl hello.xsl
AxCacheDir $TMP/axkit
+   AxGzipOutput On
 }],
 
  'AxKit XSLT Big' => ['hxsltbig.xml', qq{
@@ -593,6 +594,7 @@
AxAddStyleMap application/x-xpathscript 
+Apache::AxKit::Language::XPathScript
   AxAddProcessor text/xsl hxsltbig.xsl
AxCacheDir $TMP/axkit
+   AxGzipOutput On
 }],
 
  'AxKit XSP Hello' => ['hello.xsp', qq{
@@ -601,6 +603,7 @@
AxAddStyleMap application/x-xsp +Apache::AxKit::Language::XSP
AxAddProcessor application/x-xsp NULL
   AxCacheDir $TMP/axkit
+   AxGzipOutput On
  }],
 
  'AxKit XSP 2000' => ['h2000.xsp', qq{
@@ -609,6 +612,7 @@
AxAddStyleMap application/x-xsp +Apache::AxKit::Language::XSP
AxAddProcessor application/x-xsp NULL
   AxCacheDir $TMP/axkit
+   AxGzipOutput On
  }],
 
 # new Embperl 2.x series


[2002-10-15 00:16:53] Found apache web server at /usr/local/sbin/httpd_perl
[2002-10-15 00:16:53]  running 1 groups of benchmarks for 1 seconds
[2002-10-15 00:16:56] testing AxKit v1.6 XSP 2000 at 
http://localhost:5000/h2000.xsp?title=Hello%20World%202000&integer=2000
[2002-10-15 00:17:11] testing AxKit v1.6 XSP Hello at http://localhost:5000/hello.xsp
[2002-10-15 00:17:25] testing AxKit v1.6 XSLT Hello at http://localhost:5000/hxslt.xml
[2002-10-15 00:17:40] testing AxKit v1.6 XSLT Big at http://localhost:5000/hxsltbig.xml

Test Name   Test File  Hits/sec   # of Hits  Time(sec)  
secs/Hit   Bytes/Hit  
-   -  -  -  -  
-  -  
AxKit v1.6 XSP 2000 h2000.xsp14.8 20   1.35 
0.067600   28680  
AxKit v1.6 XSP Hellohello.xsp   245.5261   1.06 
0.004073   353
AxKit v1.6 XSLT Hello   hxslt.xml   157.6169   1.07 
0.006343   331
AxKit v1.6 XSLT Big hxsltbig.x   37.3 38   1.02 

Re: code evaluation in regexp failing intermittantly

[Ed]

On Wed, Oct 23, 2002 at 02:24:48PM -0500, Rodney Hampton wrote:
> 
> Can any of you gurus please help!
> 

A wise guru would help by directing you to:
http://perl.apache.org/docs/tutorials/tmpl/comparison/comparison.html

Re: Random broken images when generating dynamic images

[Ed]

On Wed, Oct 23, 2002 at 05:55:05PM -0500, Dave Rolsky wrote:
> So here's the situation.
> 
> I have some code that generates images dynamically.  It works, mostly.
> 
> Sometimes the image will show up as a broken image in the browser.  If I
> reload the page once or twice, the image comes up fine.
> 
> On a page with 5 different dynamic images (all generated by the same chunk
> of code, it's a set of graphs), I'll often see 1 or 2 as a broken image,
> but the rest work.  Sometimes all 5 are ok.
> 
> I tried out a scheme of writing them to disk with dynamically generated
> files, but since I still need to do some auth checking, they end up being
> served dynamically and I have the same problem.
> 
> To make it even weirder, I just took a look at one of the image files that
> showed up as broken, and it's fine (I can't view it directly in my
> browser).

I've seen the problem before.  My solution was to save the dynamic images
on disk and serve them just like plain 'ol static files from the front-end
server. This way everything is served from the same "Keep-Alive" request.
And apache does all the http/1.1 headers/chunked-encoding for me.

Your MaxKeepAliveRequests would then be the culprit on your end but not likely
unless its set really low.  I'm not sure how the browser determines the
equivalent limit. tcpdump showed that opera created a second keep-alive
request after 10 images for me (could be limiting on bytes rather than
requests ... don't know).

You can still serve dynamicly and handle the custom auth w/ the backend and
maintain the clients keep-alive.  The current mod_proxy will maintain the
clients keep-alive eventhough your backend has keepalive off.  Be sure
all the required http/1.1 components/headers are sent to maintain a
keep-alive.

I'm interested in what you finally work out.

thanks,
Ed

Re: repost: [mp1.0] recurring segfaults on mod_perl-1.27/apache-1.3.26

[Ed]

Daniel,

Could be bad hardware.  Search google for Signal 11.

Probably your memory (usual cause I've seen).

good luck.

Ed

On Tue, Oct 08, 2002 at 09:46:16AM -0700, [EMAIL PROTECTED] wrote:
> Sorry for the repost, but no responses so far, and I need some help with 
> this one.
> 
> I've managed to get a couple of backtraces on a segfault problem we've
> been having for months now. The segfaults occur pretty rarely on the
> whole, but once a client triggers one on a particular page, they do not
> stop. The length and content of the request are key in making the
> segfaults happen. Modifying the cookie or adding characters to the
> request line causes the segfaults to stop.
> 
> example (word wrapped):
> 
> 
> This request will produce a segfault (backtrace in attached gdb1.txt)
> and about 1/3 of the expected page :
> 
> 
> nc 192.168.1.20 84
> GET /perl/section/entcmpt/ HTTP/1.1
> User-Agent: Mozilla/5.0 (compatible; Konqueror/3; Linux 2.4.18-5)
> Pragma: no-cache
> Cache-control: no-cache
> Accept: text/*, image/jpeg, image/png, image/*, */*
> Accept-Encoding: x-gzip, gzip, identity
> Accept-Charset: iso-8859-1, utf-8;q=0.5, *;q=0.5
> Accept-Language: en
> Host: 192.168.1.20:84
> Cookie:
> 
>mxstsn=1033666066:19573.19579.19572.19574.19577.19580.19576.19558.19560.19559.19557.19567.19566.19568.19544.19553.19545.19551.19554.19546.19548.19547.19532.19535.19533.19538.19534:0;
> 
> 
> Apache=192.168.2.1.124921033666065714
> 
> 
> Adding a bunch of zeroes to the URI (which does not change the code
> functionality) causes the page to work correctly:
> 
> 
> nc 192.168.1.20 84
> GET
> /perl/section/entcmpt/? 
> 
> HTTP/1.1
> User-Agent: Mozilla/5.0 (compatible; Konqueror/3; Linux 2.4.18-5)
> Pragma: no-cache
> Cache-control: no-cache
> Accept: text/*, image/jpeg, image/png, image/*, */*
> Accept-Encoding: x-gzip, gzip, identity
> Accept-Charset: iso-8859-1, utf-8;q=0.5, *;q=0.5
> Accept-Language: en
> Host: 192.168.1.20:84
> Cookie:
> 
>mxstsn=1033666066:19573.19579.19572.19574.19577.19580.19576.19558.19560.19559.19557.19567.19566.19568.19544.19553.19545.19551.19554.19546.19548.19547.19532.19535.19533.19538.19534:0;
> 
> 
> Apache=192.168.2.1.124921033666065714
> 
> 
> 
> 
> Some info:
> /usr/apache-perl/bin/httpd -l
> Compiled-in modules:
>http_core.c
>mod_env.c
>mod_log_config.c
>mod_mime.c
>mod_negotiation.c
>mod_status.c
>mod_include.c
>mod_autoindex.c
>mod_dir.c
>mod_cgi.c
>mod_asis.c
>mod_imap.c
>mod_actions.c
>mod_userdir.c
>mod_alias.c
>mod_access.c
>mod_auth.c
>mod_so.c
>mod_setenvif.c
>mod_php4.c
>mod_perl.c
> 
> 
> 
> Please forgive any obvious missing info (i'm not a c programmer). The
> first backtrace shows the segfault happening in mod_perl_sent_header(),
> and the second shows it happening in  the ap_make_array() which was from
> Apache::Cookie. I don't have one handy now, but I've also seen it happen
> in ap_soft_timeout() after an XS_Apache_print (r->server was out of bounds).
> 
> I've added a third backtrace where r->content_encoding contains the
> above 'mxstsn' cookie name.
> 
> 
> 
> 
> Any help would be greatly appreciated.
> 
> -- 
> --
> Daniel Bohling
> NewsFactor Network
> 

> [root@proxy dumps]# gdb  /usr/apache-perl/bin/httpd core.12510
> GNU gdb Red Hat Linux (5.2-2)
> Copyright 2002 Free Software Foundation, Inc.
> GDB is free software, covered by the GNU General Public License, and you are
> welcome to change it and/or distribute copies of it under certain conditions.
> Type "show copying" to see the conditions.
> There is absolutely no warranty for GDB.  Type "show warranty" for details.
> This GDB was configured as "i386-redhat-linux"...
> Core was generated by `/usr/apache-perl/bin/httpd'.
> Program terminated with signal 11, Segmentation fault.
> Reading symbols from /lib/libpam.so.0...done.
> Loaded symbols for /lib/libpam.so.0
> Reading symbols from /usr/lib/libmysqlclient.so.10...done.
> Loaded symbols for /usr/lib/libmysqlclient.so.10
> Reading symbols from /lib/libcrypt.so.1...done.
> Loaded symbols for /lib/libcrypt.so.1
> Reading symbols from /lib/libresolv.so.2...done.
> Loaded symbols for /lib/libresolv.so.2
> Reading symbols from /lib/i686/libm.so.6...done.
> Loaded symbols for /lib/i686/libm.so.6
> Reading symbols from /lib/libdl.so.2...done.
> Loaded symbols for /lib/libdl.so.2
> Reading symbols from /lib/libnsl.so.1...done.
> Loaded symbols for /li

Re: repost: [mp1.0] recurring segfaults on mod_perl-1.27/apache-1.3.26

[Ed]

On Fri, Oct 18, 2002 at 03:54:22PM -0400, Perrin Harkins wrote:
> Ed wrote:
> >Could be bad hardware.  Search google for Signal 11.
> 
> That's actually pretty rare.  Segfaults are usually just a result of 
> memory-handling bugs in C programs.

I saw the problem when someone had their memory speed too low in their
bios using an asus-a7v motherboard.  Apps such as bzip2 croaked and memory
intensive compiles failed in random places.

very similar to the first answer here: http://www.bitwizard.nl/sig11/

When we were trying to debug, the failures were a giant mystery.
We spent days inside of gdb and such trying to figure out what the
heck was up.  It turns out the bios reset to incorrect settings after a
power failure and took a week or so till the random sig 11's showed up.

It was at a remote colocation too ... (checking the bios was last on our list)
We ended up replacing the box at the colo ... this melted/sig11 box is still
able to run netbsd with the bios under-clocked (up 183 days) but they dont
use it for anything important

Anyway I have a story about a bad nic cable too  but will save it

/me paronoid about mysterious sig 11's ...

Ed

Re: Random broken images when generating dynamic images

[Ed]

On Wed, Oct 23, 2002 at 05:55:05PM -0500, Dave Rolsky wrote:
> So here's the situation.
> 
> I have some code that generates images dynamically.  It works, mostly.
> 
> Sometimes the image will show up as a broken image in the browser.  If I
> reload the page once or twice, the image comes up fine.
> 
> On a page with 5 different dynamic images (all generated by the same chunk
> of code, it's a set of graphs), I'll often see 1 or 2 as a broken image,
> but the rest work.  Sometimes all 5 are ok.
> 
> I tried out a scheme of writing them to disk with dynamically generated
> files, but since I still need to do some auth checking, they end up being
> served dynamically and I have the same problem.
> 
> To make it even weirder, I just took a look at one of the image files that
> showed up as broken, and it's fine (I can't view it directly in my
> browser).

I've seen the problem before.  My solution was to save the dynamic images
on disk and serve them just like plain 'ol static files from the front-end
server. This way everything is served from the same "Keep-Alive" request.
And apache does all the http/1.1 headers/chunked-encoding for me.

Your MaxKeepAliveRequests would then be the culprit on your end but not likely
unless its set really low.  I'm not sure how the browser determines the
equivalent limit. tcpdump showed that opera created a second keep-alive
request after 10 images for me (could be limiting on bytes rather than
requests ... don't know).

You can still serve dynamicly and handle the custom auth w/ the backend and
maintain the clients keep-alive.  The current mod_proxy will maintain the
clients keep-alive eventhough your backend has keepalive off.  Be sure
all the required http/1.1 components/headers are sent to maintain a
keep-alive.

I'm interested in what you finally work out.

thanks,
Ed

Re: More Segfaultage - FreeBSD, building apache, ssl, mod_perl from ports

[Ed]

On Tue, Nov 12, 2002 at 04:29:19PM +, Rafiq Ismail (ADMIN) wrote:
> I'm a bit irritated by FreeBSD ports at the moment and need somoene to
> shine some light.  I need to build Apache from ports on a BSD box - it has
> to be from ports - but i don't want to include mod_perl in as a dso.
> Thus, I'd like to go to ports and 'Make' with a bunch of options which
> will compile mod_perl straight into my apache1.3-ssl package.  Having run
> make on www/apache1.3-ssl and www/mod_perl, all I get is segfaults.  I
> simply want to run one make to build it in one go.
> 
> How???
> 
> I'm sure that the BSD users amoungst you have all done it 101 times.
> 
> Help please?

Attached is a port i use for OpenBSD. (It needs cleaning, but works for me)

There are a bunch of "customizations" but some key points to the Makefile are:

DISTFILES=
PATCH_LIST_SUP=
FAKE_FLAGS=
post-patch:

Ed.



www-mod_perl.tar.gz
Description: application/tar-gz

Re: Image Magick Alternatives?

[Ed]

On Mon, Feb 18, 2002 at 09:26:57PM -, Jonathan M. Hollin wrote:
> The WYPUG migration from Win2K to Linux is progressing very nicely.
> However, despite my best efforts, I can't get Perl Magick to work
> (Image::Magick compiled successfully and without problems).  All I use
> Perl Magick for is generating thumbnails (which seems like a waste
> anyway).  So, is there an alternative - a module that will take an image
> (gif/jpeg) and generate a thumbnail from it?  I have searched CPAN but
> haven't noticed anything suitable.  If not, is there anyone who would be
> willing to help me install Perl Magick properly?

Imager can do what you want. many formats, antialias, freetype, etc.

Ed

pod and EmbPerl

[Ed Park]

Does anyone know whether it is possible to pod-ify an EmbPerl document?

When embedding pod directives in my EmbPerl pages and then running pod2html
on them, the pod2html interpreter returns a blank page.

thanks,
Ed

RE: :Oracle && Apache::DBI

[Ed Park]

Ian--

I very occasionally get these errors while using DBI and DBD::Oracle under
mod_perl. I find that it generally happens when a random, perfectly good SQL
statement causes the Oracle process dump the connection and write the reason
to alert.log.

Try doing the following: from your oracle home, run:
> find . -name 'alert*' -print
Go to that directory, read the alert files, and look through any
corresponding trace files. The trace files contain the sql that actually
cause the trace dump.

I find that I can usually rewrite the sql statement in such a way that it no
longer dumps core. Again, this happens _very_ rarely.

Hope this helps,
Ed

-Original Message-
From: Ian Kallen [mailto:[EMAIL PROTECTED]]
Sent: Monday, May 22, 2000 9:37 PM
To: [EMAIL PROTECTED]
Subject: DBD::Oracle && Apache::DBI



I've done everything I can think of to shore up any DB connection
flakiness but I'm still plagued by errors such as these:
DBD::Oracle::db selectcol_arrayref failed: ORA-12571: TNS:packet writer
failure
...this is only a problem under mod_perl, outside of the
mod_perl/Apache::DBI environment everything seems fine.  Once the db
connection is in this state, it's useless until the server gets a restart.

My connect strings look good and agree, I put Stas' ping method in the
DBD::Oracle::db package, set a low timeout,  called Oracle (they don't
want to hear about it).  Everything is the latest versions of
mod_perl/Apache/DBI/DBD::Oracle connecting to an Oracle 8.1.5 db on
Solaris.  Is Apache::DBI not up to it?  (it looks simple enough)

Maybe there's a better persistent connection method I should be looking
at?

--
Salon Internet  http://www.salon.com/
  Manager, Software and Systems "Livin' La Vida Unix!"
Ian Kallen <[EMAIL PROTECTED]> / AIM: iankallen / Fax: (415) 354-3326

apache.org down

[Ed Phillips]

"Hughes, Ralph" wrote:

> COOL!
> I couldn't wait...
> I built and installed mod_perl 1.24 and it fixed the problem!   Now if I can
> just get the CGI module
> to recognize my domainname .. :-)
>
> -Original Message-
> From: Hughes, Ralph
> Sent: Friday, June 02, 2000 2:02 PM
> To: Geoffrey Young; 'Michael Todd Glazier'; ModPerl
> Subject: RE: Segmetation Fault problem
>
> I'm not too good on back traces myself.   `
> I'm using a dynamic build of mod_perl, so I may try building the 1.24
> version next week sometime.
> I hadn't thought of changing the PerFreshStart parameter, it might make a
> difference...
>
> -Original Message-
> From: Geoffrey Young [mailto:[EMAIL PROTECTED]]
> Sent: Friday, June 02, 2000 1:11 PM
> To: Hughes, Ralph; 'Michael Todd Glazier'; ModPerl
> Subject: RE: Segmetation Fault problem
>
> hmmm, did you try upgrading your installation then?
> you are using a static mod_perl?
> PerlFreshRestart Off?
>
> I'm no good at reading backtraces, but posting that is probably the next
> step (see SUPPORT doc section on core dumps in the distribution)
>
> sorry I can't be of more help...
>
> --Geoff

was apache.org down

[Ed Phillips]

Level 3 is broken.

They know and are working on it. hmmm

Ed

Re: was apache.org down

[Ed Phillips]

Replying to myself.  It is back up, obviously. sorry for the noise



Ed Phillips wrote:

> Level 3 is broken.
>
> They know and are working on it. hmmm
>
> Ed

Re: [benchmark] DBI/preload (was Re: [RFC] improving memory mappingthru code exercising)

[Ed Phillips]

Yes, very cool Stas!

Perrin Harkins wrote:

> On Sat, 3 Jun 2000, Stas Bekman wrote:
>
> > correction for the 3rd version (had the wrong startup), but it's almost
> > the same.
> >
> >   Version Size   SharedDiff Test type
> >   
> > 1  3469312  2609152   860160  install_driver
> > 2  3481600  2605056   876544  install_driver & connect_on_init
> > 3  3469312  2588672   880640  preload driver
> > 4  3477504  2482176   995328  nothing added
> > 5  3481600  2469888  1011712  connect_on_init
>
> Cool, thanks for running the test!  I will put this information to good
> use...

Re: [OT now] Re: Template techniques

[Ed Phillips]

I'm just using XML on the backend for content management and as
a way to standardize what I recieve from partners and content folks,
then storing parsed content in a database from which I output text, HTML,
and/or XML.

XML::Parser suits quite fine for the above. So, Perl has plenty of XML support,
imo.

I've taken a look at what Matt is up to and I'm intrigued, but don't have a need
for it as yet.

Joshua,  what is the itch that you are scratching if you care to opine?

Ed


Drew Taylor wrote:

> Joshua Chamas wrote:
> >
> > Perrin Harkins wrote:
> > >
> > > On Fri, 9 Jun 2000, Drew Taylor wrote:
> > > > I really like the fact that templates can be compiled to perl code &
> > > > cached. Any others besides Mason & EmbPerl (and TT in the near future)?
> > >
> > > Sure: Apache::ePerl, Apache::ASP, Text::Template, and about a million
> > > unreleased modules that people wrote for their own use.  (I think writing
> > > a module that does this should be a rite of passage in Perl hacking.)
> > >
> >
> > For my second rite of passage, I'm hacking XML::XSLT
> > integration into Apache::ASP for realtime XSLT document
> > rendering with a sophisticated caching engine utilizing
> > Tie::Cache.  Moving forward, the XML buzzword seems to be
> > just about a necessity.
> >
> > Take it as a sign of respect Matt :)
> Cool! The thing that perl is missing the most right now is XML support.
> The more (and the sooner :-) packages support XML easily and natively,
> the better. I'm still an XML newbie, so all this recent perl XML
> development is very exciting for me!
>
> --
> Drew Taylor
> Vialogix Communications, Inc.
> 501 N. College Street
> Charlotte, NC 28202
> 704 370 0550
> http://www.vialogix.com/

[OT] Contract Language for free software

[Ed Phillips]

Hi All,

This is very OT, but is related to mod_perl.  I have a contract as yet
unsigned
with a Web Company to possibly rewrite their horrible perl 4 era CGI
apps
as nice  clean mostly OO mod_perl apps. It's a simple job, rather
generic.

I usually license my code with the Artistic License, so this is not a
Licensing
question, exactly. In the contract, they have sent me, they have a
paragraph
that signs the rights to all inventions over to them.

>From my perspective, what little invention there might be in these apps,

is drawn directly from freely available documentation and advice, and
the apps will of course rely heavily on CPAN modules, as well as
things I've written before. So, what I'm looking
for is advice or a paragraph that establishes that the greater part of
invention
is already public, that these programs use free software, and that
non-specific
to their business inventions, if any should be returned to the
community, etc.

I'm not a lawyer. :-) In the past, I've just ignored such paragraphs and
I've
lowered the boom in a banner at the top of my code.  But, I'd like to
put something
in any contract that I sign and these people have no idea how to deal
with free software.
They want me to sign an NDA now that I've seen their hideous spaghetti,
which is
of course full of copyright notices.  I told them that if anyone stole
this code, they would
need their head checked!

If someone has crafted any pro free software contracts that cover
invention and
they would like to share, I'd be grateful.

Cheers,

Ed

Re: [OT] Contract Language for free software

[Ed Phillips]

Please excuse the horrible formatting,
The version below should be more readable.


Ed Phillips wrote:

> Hi All,
>
> This is very OT, but is related to mod_perl.  I have a contract as yet
> unsigned
> with a Web Company to possibly rewrite their horrible perl 4 era CGI apps
> as nice  clean mostly OO mod_perl apps. It's a simple job, rather generic.
>
> I usually license my code with the Artistic License, so this is not a
> Licensing
> question, exactly. In the contract, they have sent me, they have a
> paragraph
> that signs the rights to all inventions over to them.
>
> From my perspective, what little invention there might be in these apps,
> is drawn directly from freely available documentation and advice, and
> the apps will of course rely heavily on CPAN modules, as well as
> things I've written before. So, what I'm looking
> for is advice or a paragraph that establishes that the greater part of
> invention
> is already public, that these programs use free software, and that
> non-specific
> to their business inventions, if any should be returned to the community,
> etc.
>
> I'm not a lawyer. :-) In the past, I've just ignored such paragraphs and
> I've
> lowered the boom in a banner at the top of my code.  But, I'd like to put
> something
> in any contract that I sign and these people have no idea how to deal with
> free software.
> They want me to sign an NDA now that I've seen their hideous spaghetti,
> which is
> of course full of copyright notices.  I told them that if anyone stole
> this code, they would
> need their head checked!
>
> If someone has crafted any pro free software contracts that cover
> invention and
> they would like to share, I'd be grateful.
>
> Cheers,
>
> Ed

Re: [OT] [JOB] mod_perl and Apache developers wanted

[Ed Phillips]

It is interesting and and somewhat ironic that the Engineering
dep at eToys is part of the open source community and culture
while their management's behavior was so disastrously misguided
and so misunderstanding of net culture and precedent.
They shot themselves in the foot pretty badly.

Would eToys have paid for the legal expenses of the Etoy group
if they weren't clued in by their Engineering department? Have
they learned a hard lesson?

Perrin is an exemplary figure, and I commiserate with him, but
some basic precedents of net culture need to be respected for the
network to function and the culture to flourish. If we had not
protested the attempted eToys domain grab, and I was one
who protested, they may have never recanted and  Etoy might
still be fighting at absurd personal cost.

Cheers,

Ed




Paul Singh wrote:

> Regardless of what eToys' intentions were, the way I see it, this was a case
> in which a billion dollar corporation (well, at least it was back then)
> filed suit against a handful of artists who had the etoy.com domain way
> before eToys came along.  eToys had no legitimate stake to the domain... and
> I don't associate legitimacy with the law... they seldom coincide.  So if
> this isn't a case of the bigger guy bullying the little guy, what is it?
> Granted, I have a distant association with the eToy crew so my opinions will
> be biased... however, even with staying to the facts and ignoring eToys'
> motivations, their actions alone reek of unfairness (at best).
>
> Of course, this says little of what type of work environment eToys is and
> the people that work there... but it does comment on the corporation and the
> people running it.
>
> But as you said, this is definitely off-topic, and I will cease further
> comment... take care.
>
> - jps
>
> > -Original Message-
> > From: Perrin Harkins [mailto:[EMAIL PROTECTED]]
> > Sent: Friday, June 16, 2000 4:48 PM
> > To: Paul Singh
> > Cc: ModPerl Mailing List
> > Subject: RE: [OT] [JOB] mod_perl and Apache developers wanted
> >
> >
> > On Thu, 15 Jun 2000, Paul Singh wrote:
> > > While that may be true (as with many publications), I hope you're not
> > > denying the facts of this case
> >
> > The basic facts are correct: eToys received complaints from parents about
> > the content their children found on the etoy.com site and, after failing
> > to reach an agreement with the site's operators, filed a lawsuit involving
> > trademarks which led to etoy being ordered to shut down their site by a
> > judge.
> >
> > Slashdot's coverage ignored or underreported some aspects of the situation
> > (the motivation behind the lawsuit, epxloitation of the name confusion on
> > the part of etoy), and reported some conjecture and pure flights of fancy
> > as fact (evil intentions, scheming lawyers).  You have no idea how painful
> > it is to read things like that from a source that you trust and consider
> > part of your community.  I guess I should have known better though:
> > Slashdot is an op/ed site.  If you want the news, you still have to read
> > the New York Times (who had much more accurate coverage of the events).
> >
> > Anyway, I don't claim that eToys was right to take legal action, just that
> > the reports about an evil empire were greatly exaggerated and that eToys
> > is a good place to work, full of good people.  Anyone who doesn't believe
> > me at this point probably never will, so I'm going to stop spamming the
> > list about this subject and go back to spamming about mod_perl.
> >
> > - Perrin
> >

RE: setting LD_LIBRARY_PATH via PerlSetEnv does not work

[Ed Park]

I ran into this exact same problem this weekend using:
-GNU ld 2.9.1
-DBD::Oracle 1.06
-DBI 1.14
-RH Linux 6.0
-Oracle 8i

Here's another, cleaner (I think) solution to your problem: after running
perl Makefile.PL, modify the resulting Makefile as follows:
1. search for the line LD_RUN_PATH=
2. replace it with LD_RUN_PATH=(my_oracle_home)/lib
(my_oracle_home) is, of course, the home path to your oracle installation.
In particular, the file libclntsh.so.8.0 should exist in that directory.
(If you use cpan, the build directory for DBD::Oracle should be in
~/.cpan/build/DBD-Oracle-1.06/ if you're logged in as root.)

Then, just type make install, and all should go well.

FYI, setting LD_RUN_PATH has the effect of hard-coding the path to
(my_oracle_home)/lib in the resulting Oracle.so file generated by the
DBD::Oracle so that at run-time, it doesn't have to go searching through
LD_LIBRARY_PATH or the default directories used by ld.

The reason I think this is cleaner is because this way, the Oracle directory
is not hardcoded globally into everyone's link paths, which is what ldconfig
does.

For more information, check out the GNU man page on ld:
http://www.gnu.org/manual/ld-2.9.1/html_mono/ld.html
or an essay on LD_LIBRARY_PATH:
http://www.visi.com/~barr/ldpath.html

cheers,
Ed

-Original Message-
From: Stas Bekman [mailto:[EMAIL PROTECTED]]
Sent: Monday, August 21, 2000 6:51 AM
To: Richard Chen
Cc: Yann Ramin; [EMAIL PROTECTED]
Subject: Re: setting LD_LIBRARY_PATH via PerlSetEnv does not work


On Mon, 21 Aug 2000, Richard Chen wrote:

> It worked like a charm! If PerlSetEnv could not do it, I think
> this should be documented in the guide. I could not find any mention

done. thanks for the tip!

> about ldconfig in the modperl guide. May be I missed it somehow.
>
> The procedure on linux is very simple:
> # echo $ORACLE_HOME/lib >> /etc/ld.so.conf
> # ldconfig
>
> Thanks
>
> Richard
>
> On Sun, Aug 20, 2000 at 08:11:50PM -0700, Yann Ramin wrote:
> > As far as FreeBSD goes, LD_LIBRARY_PATH is not searched for setuid
> > programs (aka, Apache). This isn't a problem for CGIs since they don't
> > do a setuid (and are forked off), but Apache does, and mod_perl is in
> > Apache.  I think thats right anyway :)
> >
> > You could solve this globaly by running ldconfig (I assume Linux has it,
> > FreeBSD does).  You'd be looking for:
> >
> > ldconfig -m 
> >
> > Hope that helps.
> >
> > Yann
> >
> > Richard Chen wrote:
> > >
> > > This is a redhat linux 6.2 box with perl 5.005_03, Apache 1.3.12,
> > > mod_perl 1.24, DBD::Oracle 1.06, DBI 1.14 and oracle 8.1.6.
> > > For some odd reason, in order to use DBI, I have to set
> > > LD_LIBRARY_PATH first. I don't think I needed to do this when I
> > > used oracle 7. This is fine on the command line because
> > > I can set it in the shell environment. For cgi scripts,
> > > the problem is also solved by using apache SetEnv directive. However,
> > > this trick does not work under modperl. I had tried PerlSetEnv
> > > to no avail. The message is the same as if the LD_LIBRARY_PATH is not
set:
> > >
> > > install_driver(Oracle) failed: Can't load
> > > '/usr/lib/perl5/site_perl/5.005/i386-linux/auto/DBD/Oracle/Oracle.so'
for module DBD::Oracle:
> > > libclntsh.so.8.0: cannot open shared object file: No such file or
directory at
> > > /usr/lib/perl5/5.00503/i386-linux/DynaLoader.pm line 169. at (eval 27)
line 3 Perhaps a required shared
> > > library or dll isn't installed where expected at
/usr/local/apache/perl/tmp.pl line 11
> > >
> > > Here is the section defining LD_LIBRARY_PATH under Apache::Registry:
> > >
> > > PerlModule Apache::Registry
> > > Alias /perl/ /usr/local/apache/perl/
> > > 
> > >   PerlSetEnv LD_LIBRARY_PATH /u01/app/oracle/product/8.1.6/lib
> > >   SetHandler perl-script
> > >   PerlHandler Apache::Registry
> > >   Options ExecCGI
> > >   PerlSendHeader On
> > >   allow from all
> > > 
> > >
> > > Does anyone know why PerlSetEnv does not work in this case?
> > > How come SetEnv works for cgi scripts? What is the work around?
> > >
> > > Thanks for any info.
> > >
> > > Richard
> >
> > --
> >
> > 
> > Yann Ramin  [EMAIL PROTECTED]
> > Atrus Trivalie Productions  www.redshift.com/~yramin
> > Monterey High ITwww.montereyhigh.com
> > ICQ 46805627
> > AIM  

Re: OT: Server-push client page reload

[ed phillips]

A very impressive 95 lines o' Perl Randal!

Ed



"Randal L. Schwartz" wrote:

> >>>>> "Michael" == Michael Nachbaur <[EMAIL PROTECTED]> writes:
>
> Michael> This is off-topic, but I need an answer pretty quick, and I
> Michael> *am* writing this app using mod_perl, so its sorta related
> Michael> (also, I don't want the headache of re-subscribing to a new
> Michael> list).
>
> Michael> You know those online web-based tech support chat systems?
> Michael> Its commonly frame based, but its just like IRC, but over
> Michael> HTML.  when a user posts a message it immediatly pops up on
> Michael> the chat frame, and you submit your message through a
> Michael> regular-ol' HTML form.  I don't think this is an applet,
> Michael> because this works in all sorts of browsers.  I think its
> Michael> javascript, but I'm not sure. My main question, is when the
> Michael> server knows that a new message has been posted, how does it
> Michael> push that new page out to the client web browser?  I'm used
> Michael> to all page-views originating from the client...not the
> Michael> server.
>
> Michael> Any ideas?
>
> Server push is not universal.  Client Pull is more available.
> See <http://www.perlmonks.org/index.pl?node_id=31083> for an example
> of a very short client-pull webchat, from an upcoming WebTechniques
> column (past columns at <http://www.stonehenge.com/merlyn/WebTechniques/>).
>
> --
> Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
> <[EMAIL PROTECTED]> http://www.stonehenge.com/merlyn/>
> Perl/Unix/security consulting, Technical writing, Comedy, etc. etc.
> See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!

Re: open(FH,'|qmail-inject') fails

[ed phillips]

Greg Stark wrote:

> A better plan for such systems is to have a queue in your database for
> parameters for e-mails to send. Insert a record in the database and let your
> web server continue processing.
>
> Have a separate process possibly on a separate machine or possibly on multiple
> machines do selects from that queue and deliver mail. I think the fastest way
> is over a single SMTP connection to the mail relay rather than forking a
> process to inject the mail.
>
> This keeps the very variable -- even on your own systems -- mail latency
> completely out of the critical path for web server requests. Which is really
> the key measure that dictates the requests/s you can serve.
>

Exactly, Greg.  This is homologous to proxy serving http requests. Ideally, the
data/text
should be relayed to a separate, dedicated mail server.  This has come up
repeatedly
for me on performance tuning projects. If there are a number of mail processes
negotiating
with remote hosts even running on the same machine as you are web serving from,
you may,
under significant load, degrade performance.

Re: Forking in mod_perl?

[ed phillips]

Hi David,

Check out the guide at

http://perl.apache.org/guide/performance.html#Forking_and_Executing_Subprocess

The Eagle book also covers the C API subprocess details on page 622-631.

Let us know if the guide is unclear to you, so we can improve it.

Ed


"David E. Wheeler" wrote:

> Hi All,
>
> Quick question - can I fork off a process in mod_perl? I've got a piece
> of code that needs to do a lot of processing that's unrelated to what
> shows up in the browser. So I'd like to be able to fork the processing
> off and return data to the browser, letting the forked process handle
> the extra processing at its leisure. Is this doable? Is forking a good
> idea in a mod_perl environment? Might there be another way to do it?
>
> TIA for the help!
>
> David
>
> --
> David E. Wheeler
> Software Engineer
> Salon Internet ICQ:   15726394
> [EMAIL PROTECTED]   AIM:   dwTheory

Re: Forking in mod_perl?

[ed phillips]

I hope it is clear that you don't want fork the whole server!

Mod_cgi goes to great pains to effectively fork a subprocess, and
was the major impetus I believe for the development of
the C subprocess API. It  (the source code for
mod_cgi) is a great place to learn some of the
subtleties as the Eagle book points out. As the Eagle book
says, Apache is a complex beast. Mod_perl gives
you the power to use the beast to your best advantage.

Now you are faced with a trade off.  Is it more expensive to
detach a subprocess, or use the child cleanup phase to do
some extra processing? I'd have to know more specifics to answer
that with any modicum of confidence.

Cheers,

Ed


"David E. Wheeler" wrote:

> ed phillips wrote:
> >
> > Hi David,
> >
> > Check out the guide at
> >
> > http://perl.apache.org/guide/performance.html#Forking_and_Executing_Subprocess
> >
> > The Eagle book also covers the C API subprocess details on page 622-631.
> >
> > Let us know if the guide is unclear to you, so we can improve it.
>
> Yeah, it's a bit unclear. If I understand correctly, it's suggesting
> that I do a system() call and have the perl script called detach itself
> from Apache, yes? I'm not too sure I like this approach. I was hoping
> for something a little more integrated. And how much overhead are we
> talking about getting taken up by this approach?
>
> Using the cleanup phase, as Geoffey Young suggests, might be a bit
> nicer, but I'll have to look into how much time my processing will
> likely take, hogging up an apache fork while it finishes.
>
> Either way, I'll have to think about various ways to handle this stuff,
> since I'm writing it into a regular Perl module that will then be called
> from mod_perl...
>
> Thanks,
>
> David

Re: Apache trouble reading in large cookie contents

[ed phillips]

Explictly echoing Gunther, don't go there!

Use cookies, think crumbs of info, as flyweights.  Significant chunks of data need
to be passed and stored
in other ways.

Ed

Gunther Birznieks wrote:

> Caveat: even if you modify apache to do larger cookies, it's possible that
> there will be a set of browsers that won't support it.
>
> At 04:48 PM 10/20/00 -0700, ___cliff rayman___ wrote:
> >i'm not an expert with this, but, a quick grep for your error in
> >the apache source (mine is still 1.3.9 ) and some digging yield:
> >
> >./include/httpd.h:#define DEFAULT_LIMIT_REQUEST_FIELDSIZE 8190
> >
> >so you're right, 8K is currently the apache limit. if you try to change
> >this value in
> >the source code, you will probably also have to muck with IOBUFSIZE and
> >possibly other things as well.  IOBUFSIZE is 8192 and the
> >DEFAULT_LIMIT_REQUEST_FIELDSIZE is set to 2 bytes below that to make
> >room for the extra \r\n after the last header.
> >
> >looks like you'll have to take responsibility for mucking with the apache
> >source, or
> >sending smaller cookies and using some other techniques such as HIDDEN fields.
> >
> >
> >--
> >___cliff [EMAIL PROTECTED]http://www.genwax.com/
> >
> >"Biggs, Jody" wrote:
> >
> > > I'm having trouble when a browser sends a fair sized amount of data to
> > > Apache as cookies - say around 8k.
> > >
> >
> > > Apache then complains (and fails the request) with
> > > a message of the sort:
> >
> > > [date]  [error] [client 1.2.3.4] request failed: error reading the headers
> >
> > > I assume this is due to a compile time directive to Apache specifying the
> > > maximum size of a header line.
> > >
>
> __
> Gunther Birznieks ([EMAIL PROTECTED])
> eXtropia - The Web Technology Company
> http://www.extropia.com/

[Http-webtest-general] [ANNOUNCE] HTTP-WebTest-Plugin-TagAttTest-1.00

[Ed Fancher]

The uploaded file    
HTTP-WebTest-Plugin-TagAttTest-1.00.tar.gzhas entered CPAN 
as  file: 
$CPAN/authors/id/E/EF/EFANCHE/HTTP-WebTest-Plugin-TagAttTest-1.00.tar.gz  
size: 5312 bytes   md5: 940013aada679fdc09757f119d70686e
 
 
NAME    HTTP::WebTest ::Plugin::TagAttTest - WebTest 
plugin providing a higher level tag and attribute search interface.
 
DESCRIPTION    see also http://search.cpan.org/search?query=HTTP%3A%3AWebTest&mode=all    
This module is a plugin extending the functionality of the WebTest module to 
allow tests of the form:
my $webpage='http://www.ethercube.net'; my @result;
 
 @result = (@result, {test_name => "title 
junk", url   
=> 
$webpage, tag_forbid 
=> [{ tag=>"title", tag_text=>"junk"}]}); @result = (@result, 
{test_name => "title test 
page", url   
=> 
$webpage, tag_require 
=> [{tag=> "title", text=>"test page"}]}); @result = (@result, 
{test_name => "type att with xml in 
value", url   
=> 
$webpage, tag_forbid 
=> [{attr=>"type", attr_text=>"xml" }]}); @result = (@result, 
{test_name => "type class with body in 
value", url   
=> 
$webpage, tag_require 
=> [{attr=>"class", attr_text=>"body" }]}); @result = 
(@result, {test_name => "class 
att", url   
=> 
$webpage, tag_require 
=> [{attr=>"class"}]}) ; @result = (@result, {test_name 
=> "script 
tag", url   
=>$webpage, tag_forbid 
=> [{tag=> "script"}]}); @result = (@result, {test_name => 
"script tag with attribute 
language=_javascript_", url   
=> 
$webpage, tag_forbid 
=> 
[{tag=>"script",attr=>"language",attr_text=>"_javascript_"}]}) ; my 
[EMAIL PROTECTED];
 
    my $params = { 
    
plugins => 
["::FileRequest","HTTP::WebTest::Plugin::TagAttTest"] 
};my $webtest= HTTP::WebTest->new;#4check_webtest(webtest 
=>$webtest, tests=>  $tests,opts=>$params, 
check_file=>'t/test.out/1.out');#$webtest->run_tests(  
$tests,$params);
 
Ed FancherEthercube Solutionshttp://www.ethercube.netPHP, Perl, 
MySQL, _javascript_ solutions.

Re: Working directory of script is "/" !

[Ed Grimm]

On Wed, 30 Jul 2003, Stas Bekman wrote:

> Perrin Harkins wrote:
>> On Tue, 2003-07-29 at 07:23, Stas Bekman wrote:
>> 
>>>That's correct. This is because $r->chdir_file in compat doesn't do
>>>anything.  The reason is that under threaded mpm, chdir() affects all
>>>threads. Of course we could check whether the mpm is prefork and do
>>>things the old way, but that means that the same code won't work the
>>>same under threaded and non-threaded mpms. Hence the limbo. Still
>>>waiting for Arthur to finish porting safecwd package, which should
>>>resolve this problem.
>> 
>> When he does finish it, won't we make the threaded MPM work just like
>> this?  It seems like it would be reasonable to get prefork working
>> properly, even if the threaded MPM isn't ready yet. 
> 
> It's a tricky thing. If we do have a complete implementation then it's
> cool.  If not then we have a problem with people testing their code on
> prefork mpm and then users getting the code malfunctioning on the
> threaded mpms.
> 
> I think we could have a temporary subclass of the registry (e.g.:
> ModPerl::RegistryPrefork) which will be removed once the issue is
> resolved. At least it'll remind the developers that their code won't
> work on the threaded mpm setups. However if they make their code
> working without relying on chdir then they can use Modperl::Registry
> and the code will work everywhere.

What's wrong with having the chdir code check for the threaded mpm, and,
if it detects it, generate a warning that describes the situation?

Admittedly, I have a difficult time understanding someone who tests
under one mpm, and then releases under another mpm without testing.  I
realize there are people who do this sort of thing; I'm merely stating
that I have difficulty understanding them.

Ed

RE: sybase / mod_perl / linux question? [OFFTOPIC]

[Ed Park]

Interesting.

I tested an identical setup of Apache/modperl/Embperl/Oracle on NT and
Linux, and I experienced a huge slowdown on NT. When I looked into it, I
found that the more database-intensive the page, the slower the relative
performance of the NT platform. I took that to mean that it was actually
Oracle on NT that was the root of the problem, but wasn't sure. I guess now
I know.

-Ed

>Doesn't seem to have hindered it in any way for me. Linus has
> discussed raw
> partitions several times - the upshot being that they tend to be no faster
> than using e2fs because e2fs is very fast anyway, and you'd simply have to
> implement a lot of the e2fs functions inside of your database anyway.
>
> Anyhow - I don't know about all the internal workings of these things -
> just that it works and is damn quick for me.
>
> BTW: Someone benchmarked Oracle on Linux vs Oracle on NT (using TPC code)
> and found the Linux version to be about 4-7 (depending on the test) times
> faster. So I guess that's a finger in the eye to raw partitions (I think
> the NT version can use raw partitions - correct me if I'm wrong).
>
> --
> 
>
> Details: FastNet Software Ltd - XML, Perl, Databases.
> Tagline: High Performance Web Solutions
> Web Sites: http://come.to/fastnet http://sergeant.org
> Available for Consultancy, Contracts and Training.
>

Re: Apache::DBI & MySQL

[Ed Phillips]

Even with MySQL, persistent connections are a performance boost, although you need to 
have a reason to use them. That is, only open a persistent connection when you have 
determined that you will use that connection enough to make a difference. Other 
connections may be better, as Ken said, one-time.

Ed

weirdest bug i have seen in a long time: EmbPerl 1.2b10

[Ed Park]

First, I'd like to mention that I think EmbPerl is the greatest thing since
sliced bread, and I'd like to thank Gerald for his time and effort.

But here's an exceptionally strange bug that will cause the embperl/apache
process to seg fault:
---BEGIN SCRIPT
[-
$hello %n;
-]
END SCRIPT-

In fact, anything of the form:
.+ %n.*
will seg fault, but I have found no other combination (.* %t.*, etc.) that
will seg fault.

It's not a critical bug-- I don't know of any well-formed Perl statement
that looks like that (I found it as a bug in my program)-- but it's a
curious one. If anyone has an explanation, I'd be very interested in hearing
the answer.

My setup:
Apache/1.3.9 (Unix)
DAV/0.9.11
mod_perl/1.21
mod_ssl/2.4.2
OpenSSL/0.9.4
HTML::Embperl 1.2b10
Perl 5.00404
Linux kernel 2.0.36 (Red Hat 5.2)

cheers,
Ed

load/regression test builders, monitoring tools for mod_perl apps

[Ed Park]

Does anyone know of any good open source test builders for
regression/performance-testing a mod_perl app?

This is the essence of what I would want such a suite to do:
RECORD:
-set up a proxy server to forward HTTP requests to a mod_perl'd server.
-capture all GET/POST requests from the client and log them to a file, along
with the server's output. The server's output would be the 'master' copy.
PLAYBACK (REGRESSION):
-play back the GET/POST requests and capture the output. Compare the output
against the master copy. Raise an error in the log file if the two differ.
PLAYBACK (LOAD):
-play back the GET/POST requests according to some load scheme to see how
well the application holds up under load.

If this doesn't exist, I think it would be easy enough to write using LWP; I
just don't want to duplicate anyone's efforts.

I'd also be interested to know if anyone knows of any good webserver
monitoring programs that could automatically kill spinning httpds, short of
a CRON job. FYI-- I have encountered mystery spinning httpd's as well, but I
have always been able to pin it down on bad/risk code or thrashing. At any
rate, I still need to be able to kill spinning httpds should it come to
that.

cheers,
Ed

Re: Server Stats

[Ed Phillips]

>this is like closing the gate after the horse has bolted without things
>like decent locking and transactions. Although perhaps I'm mistaken and

You can rest assured that they know what they are doing. :-)

It is also worth upgrading to newer versions. The newest versions not deemed stable 
just yet no longer use ISAM, are much faster, and will allow for a host of new 
features. stay tuned.

ed

Re: Spreading the load across multiple servers (was: Server Stats)

[Ed Phillips]

>I don't have any real answers - just a suggestion. What is wrong with the
>classic RDBMS architecture of RAID 1 on multiple drives with MySQL - surely
>it will be able to do that transparently?


Yes, RAID is very helpful with MySQL.  I spoke with Monty, the developer of MySQL at 
the open source conference in Monterey and he said that they are currently working on 
replication and mirroring features. It might be worth inquiring directly with them. 


Ed

Re: DBI

[Ed Phillips]

This is also not a mod_perl question.

depending on where your DBD::Oracle is installed you can get away with certain 
liberties in the Oracle library department. 

Nonetheless, you should continue your inquiry on a DBI related list.

Thank you,

Ed

RE: pool of DB connections ?

[Ed Park]

Oleg--

I don't know that this will help, but you could try using DBI::Proxy. The
setup would theoretically be as follows: each apache process uses DBI::Proxy
as the client;  each creates a network connection to DBI::ProxyServer, which
creates a few persistent connections to the db server using the
connect_cached method.

I have not tried this myself, but reference is made to it at
http://www.crystaltech.com/perldocs/lib/site/DBD/Proxy.html

For more help, you might try the DBI mailing list at
http://www.symbolstone.org/technology/perl/DBI/

good luck

-Ed

> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> Behalf Of Oleg Bartunov
> Sent: Monday, November 29, 1999 12:00 PM
> To: Leslie Mikesell
> Cc: [EMAIL PROTECTED]
> Subject: Re: pool of DB connections ?
>
>
> On Mon, 29 Nov 1999, Leslie Mikesell wrote:
>
> > Date: Mon, 29 Nov 1999 09:59:38 -0600 (CST)
> > From: Leslie Mikesell <[EMAIL PROTECTED]>
> > To: Oleg Bartunov <[EMAIL PROTECTED]>
> > Cc: [EMAIL PROTECTED]
> > Subject: Re: pool of DB connections ?
> >
> > According to Oleg Bartunov:
> >
> > > I'm using mod_perl, DBI, ApacheDBI and was quite happy
> > > with persistent connections httpd<->postgres until I used
> > > just one database. Currently I have 20 apache servers which
> > > handle 20 connections to database. If I want to work with
> > > another database I have to create another 20 connections
> > > with DB. Postgres is not multithreading
> > > DB, so I will have 40 postgres backends. This is too much.
> > > Any experience ?
> >
> > Try the common trick of using a lightweight non-mod_perl apache
> > as a front end, proxying the program requests to a mod_perl
> > backend on another port.  If your programs live under directory
> > boundaries you can use ProxyPass directives. If they don't you
> > can use RewriteRules with the [p] flag to selectively proxy
> > (or [L] to not proxy).  This will probably allow you to cut
> > the mod_perl httpd's at least in half.  If you still have a
> > problem you could run two back end httpds on different ports
> > with the front end proxying the requests that need each database
> > to separate backends.  Or you can throw hardware at the problem
> > and move the database to a separate machine with enough memory
> > to handle the connections.
>
> I didn't write all details but of course I already have 2 servers setup.
>
>   Regards,
>
>   Oleg
>
> >
> >   Les Mikesell
> >[EMAIL PROTECTED]
> >
>
> _
> Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
> Sternberg Astronomical Institute, Moscow University (Russia)
> Internet: [EMAIL PROTECTED], http://www.sai.msu.su/~megera/
> phone: +007(095)939-16-83, +007(095)939-23-83
>

Embperl problem (newbie question?)

[Ed Greenberg]

Just trying out Embperl, and I discovered that (in my test of dynamic 
tables) the $maxrow and $maxcol variables are being set to defaults of 100 
and 10 respectively and then obeyed, even though the $tabmode variable is 
set to 17.  According to the documentation, these variables should only be 
obeyed when tabmode contains bits in the 64 and 4 position.

My test called for 209 rows and 11 columns, and I was flummoxed for a bit 
until I started playing around with these variables.

Am I missing something, or is it just a documentation inconsistancy?



Ed Greenberg
__
Get Your Private, Free Email at http://www.hotmail.com

ApacheDBI vs DBI for TicketMaster

[Ed Loehr]

My apache children are seg faulting due to some combination of
DBI usage and the cookie-based authentication/authorization
scheme from chapter 6 in the "eagle" book by L. Stein and D.
MacEachern.  I have read the ApacheDBI documentation, scoured
mailing lists, deja.com, etc., but I'm hoping someone might be
able illuminate what is going on here...

The authentication/authorization process is working smoothly.
Just after a ticketed client is revalidated (ie., just after
leaving Apache::TicketAccess with success), however, the apache
child seg faults.  If I comment out all DBI references in the
Apache::Ticket* modules used for password querying,  and just
hard-code a guaranteed password match, the seg fault disappears.
Without any authentication attempts at all, DBI works smoothly.
The db connection is done within each child upon the first db
query (NOT in the main process).

In looking over ApacheDBI, it's not clear it is doing anything
significantly different in terms of the timing of connections
among children.

Any clues?

Am I missing something special that ApacheDBI does that would
prevent this problem?

Cheers,
Ed Loehr

Re: ApacheDBI vs DBI for TicketMaster

[Ed Loehr]

Randy Harmon wrote:

> On Sun, Jan 02, 2000 at 01:48:58AM -0600, Ed Loehr wrote:
> > My apache children are seg faulting due to some combination of
> > DBI usage and the cookie-based authentication/authorization
> [...]
> > child seg faults.  If I comment out all DBI references in the
>
> Hm, are you connecting to your database prior to Apache's forking - i.e., in
> your startup.pl?  That could cause trouble, especially on older versions of
> Apache and Apache::DBI.

No.  I'm only connecting in the child servers.  I verified that via PIDs in the
log file with debugging prints, and logically as well since the DBI::connect()
command is only executed during a query reached via a handler...

BTW, this is all on apache 1.3.9 with mod_ssl 2.4.9 and mod_perl 1.21 on Redhat
6.1 (2.2.12-20smp)...

Anyone else have any suspicions/ideas/leads?

Cheers,
Ed Loehr

Re: ApacheDBI vs DBI for TicketMaster

[Ed Loehr]

Edmund Mergl wrote:

> > > On Sun, Jan 02, 2000 at 01:48:58AM -0600, Ed Loehr wrote:
> > > > My apache children are seg faulting due to some combination of
> > > > DBI usage and the cookie-based authentication/authorization
> > > [...]
> > > > child seg faults.  If I comment out all DBI references in the
> > >
> > > Hm, are you connecting to your database prior to Apache's forking
> >
> > No.  BTW, this is all on apache 1.3.9 with mod_ssl 2.4.9 and mod_perl 1.21 on
> Redhat 6.1 (2.2.12-20smp)...

>
> do you use rpm's or did you compile everything by yourself ?

Compiled everything myself.  Oh, and I am also using DBD::Pg 0.92...

Does that suggest anything to anyone?

Cheers,
Ed Loehr

Re: Comparing arrays

[Ed Phillips]

Really Dheeraj,

This is not a mod_perl specific question, and I don't know the all important context 
into which this boilerplate code you are seeking to elicit from the list is to be 
dropped.

here is a boilerplate "find me keys that are not in both hashes":

foreach (keys %hash_one) {
  push(@here_not_there, $_) unless exists $hash_two{$_};  
}

shame on you. To expiate your sins, read perldoc pages for two hours
everyday for two weeks.

ed

Re: Comparing arrays

[Ed Phillips]

Cliff,

I wanted him to work for the rest of it, or at least go to another list.

It looks like he wanted two arrays, @in_hash_one_alone and @in_hash_two_alone,
so having him push to one array may confuse him. he's better off doing a little
studying, methinks.

ed

Re: mysql.pm on Apache/mod_perl/perl win98

[Ed Phillips]

Hi Dave,

I only do *nix, but I think that you should not need mysql.pm if you are using
DBI/DBD. Jochen is quite helpful on the MySQL modules list. subscription info availble 
at www.mysql.com.

Good Luck,

Ed

Re: modperl success story

[Ed Phillips]

>The troll vanisheth!

ha!

Reminds me of the Zen story of an old fisherman in a boat on a lake in a heavy can't 
see your hands fog. He bumps into another boat, and shouts at the other guy, "Look 
where you're going would you! You almost knocked me over."  He pulls up beside the 
boat and is about to give the other guy a piece of his mind, but when he looks in the 
other boat, he discovers that no one else is there.

Flame trolls on mailing lists are virtual empty boats, whose only value is the 
sometimes humorous apoplexy elicited in the old sea salts on the list.


Ed

Re: APACHE_ROOT

[Ed Phillips]

Ged,

You are very entertaining. The code in question is also known as a combined
copy and substitution.

>Beware if you haven't got /src on the end of your source directory!

If you don't have a match with the string or regexp , you'll just get a straight copy.


Ed

   X-Authentication-Warning: C2H5OH.jubileegroup.co.uk: ged owned process doing -bs
   Date: Sat, 15 Jan 2000 00:00:37 + (GMT)
   From: "G.W. Haywood" <[EMAIL PROTECTED]>
   Content-Type: TEXT/PLAIN; charset=US-ASCII
   Sender: [EMAIL PROTECTED]
   Precedence: bulk

   Hi there,

   On 14 Jan 2000, William P. McGonigle wrote:

   > Can someone explain what APACHE_ROOT is meant to be?  I'm assuming
   > it's somehow different thatn APACHE_SRC (which I'm defining).

   The expression

   ($APACHE_ROOT = $APACHE_SRC) =~ s,/src/?$,,;

   sets the scalar $APACHE_ROOT to be equal to the scalar $APACHE_SRC and
   then chops off any "/src" or "/src/" from the end of it.  
   

   The =~ binding operator (p27) tells perl to do the substitution
   s,/src/?$,, to the thing on left hand side of its expression.

   The parentheses (p77) mean the thing in them is a term, which has the
   highest precedence in perl so the assignment has to be done first.

   The substitution then has to be done on the result, $APACHE_ROOT and
   not $APACHE_SRC, er, obviously.

   The three commas are quotes (p41) for a substitution, presumably
   chosen because they can't easily appear in a filename.

   The pattern to match is

   /src/?$

   The question mark is a quantifier (p63), it says we can have 0 or 1
   trailing slash in the pattern we match - it's trailing at the end of
   a string because of the $ (p62).

   If our string matches, the matching bit is replaced with the bit
   between the second and third commas.  There's nothing between the
   second and third commas, so it's replaced with nothing.  Have a look
   at pages 72 to 74 especially for more about the s/// construct.

   The page numbers are from the Camel Book, second edition.  I keep it
   on my desk at all times, it stops my papers blowing around.  You will
   help yourself a lot with these things if you read chapters one and two
   five or six times this year as a kind of a penance.

   So if

   $APACHE_SRC eq  "/usr/local/apache/src/"

   or

   $APACHE_SRC eq  "/usr/local/apache/src"

   then

   $APACHE_ROOT eq "/usr/local/apache"

   after the substitution.

   I just *love* Perl's pattern matching!

   73,
   Ged.

Re: splitting mod_perl and sql over machines

[Ed Phillips]

>   > Most of my requests are served within 0.05-0.2 secs, but I afraid that
>   > adding a network (even a very fast one) to deliver mysql results, will
>   > make the response answer go much higher, so I'll need more httpd processes
>   > and I'll get back to the original situation where I don't have enough
>   > resources. Hints?

>   The network just has to match the load.  If you go to a switched 100M
>   net you won't add much delay.  You'll want to run persistent DBI
>   connections, of course, and do all you can with front-end proxies
>   to keep the number of working mod_perl's as low as possible.


Yes. Even under low load a 100M connected separate db server will bench
about the same performance as the intuitively "faster" unix socket connection
(for MySQL) on same box for reasons mentioned above. Special care can be taken to tune 
MySQL for the size of and type of requests as well, increasing
performance. See the MySQL docs.

I asked a question earlier about a client only(sep db) set up 
of DBD::Oracle and just which of the Oracle libraries are critical 
and which can be skipped. 

If you check the CLIENTS read me you'll see some contradictory advice. 
I'm curious about that because I'd love to minimize use of libraries
on Oracle set ups

not a mod_perl specific question so offlist would be great if any would 
be so kind.


ed

Re: oracle : The lowdown

[Ed Phillips]

For those of you tired of this thread please excuse me, but
here is MySQL's current position statement on and discussion
about transactions:

Disclaimer: I just helped Monty write this partly in response to
some of the fruitful, to me, discussion on this list. I know
this is not crucial to mod_perl but I find the "wise men who 
are enquirers into many things" to be one of the great things
about this list, to paraphrase old Heraclitus. I learn quite
a bit about quite many things by following leads and hints here
as well as by seeing others problems.

I'd love to see your criticism of the below either here or
off the list.


Ed
-


The question is often asked, by the curious and the critical, "Why is
MySQl not a transactional database?" or "Why does MySQl not support 
transactions."

MySQL has made a conscious decision to support another paradigm for 
data integrity, "atomic operations." It is our thinking and experience 
that atomic operations offer equal or even better integrity with much 
better performance. We, nonetheless, appreciate and understand the 
transactional database paradigm and plan, in the next few releases, 
on introducing transaction safe tables on a per table basis. We will 
be giving our users the possibility to decide if they need
the speed of atomic operations or if they need to use transactional 
features in their applications. 

How does one use the features of MySQl to maintain rigorous integrity 
and how do these features compare with the transactional paradigm?

First, in the transactional paradigm, if your applications are written 
in a way that is dependent on the calling of "rollback" instead of "commit" 
in critical situations, then transactions are more convenient. Moreover, 
transactions ensure that unfinished updates or corrupting activities 
are not commited to the database; the server is given the opportunity 
to do an automatic rollback and your database is saved. 

MySQL, in almost all cases, allows you to solve for potential 
problems by including simple checks before updates and by running 
simple scripts that check the databases for inconsistencies and 
automatically repair or warn if such occurs. Note that just by 
using the MySQL log or even adding one extra log, one can normally 
fix tables perfectly with no data integrity loss. 

Moreover, "fatal" transactional updates can be rewritten to
 be atomic. In fact,we will go so far as to say that all
 integrity problems that transactions solve can be done with 
LOCK TABLES or atomic updates, ensuring that 
you never will get an automatic abort from the database, which is a
common problem with transactional databases.
 
Not even transactions can prevent all loss if the server goes down.  
In such cases even a transactional system can lose data.  
The difference between different systems lies in just how small 
the time-lap is where they could lose data. No system is 100 % secure, 
only "secure enough". Even Oracle, reputed to be the safest 
of transactional databases, is reported to sometimes lose data
 in such situations.

To be safe with MySQL you only need to have backups and have the update
logging turned on.  With this you can recover from any situation that you could
with any transactional database.  It is, of course, always good to have
backups, independent of which database you use.

The transactional paradigm has its benefits and its drawbacks. Many users
and application developers depend on the ease with which they can code around
problems where an "abort" appears or is necessary, and they may have to do
 a little more work with MySQL to either think differently or write more.
 If you are new to the atomic operations paradigm, or more familiar or more
comfortable with transactions, do not jump to the conclusion that MySQL 
has not addressed these issues. Reliability and integrity are foremost 
in our minds.

Recent estimates are that there are more than 1,000,000 mysqld servers 
currently running, many of which are in production environments.  We hear
 very, very seldom from our users that they have lost any data, and in
 almost all of those cases user error is involved. This is in our 
opinion the best proof of MySQL's stability and reliability.

Lastly, in situations where integrity is of highest importance, MySQL's
 current features allow for transaction-level or 
better  reliability and integrity. 

If you lock tables with LOCK TABLES, all updates will stall until any
integrity checks are made.  If you only do a read lock (as opposed to
a write lock), then reads and inserts are still allowed to happen.
The new inserted records will not be seen by any of the clients
that have a READ lock until they relaease their read locks.
With INSERT DELAYED you can queue insert into a local queue, until
the locks are released, without having to have the client to wait for
the insert to complete.


Atomic

Can't upgrade that kind of scalar (and more)

[Ed Loehr]

I've scoured deja.com, FAQs, modperl list archives at 
forum.swarthmore.edu, 'perldoc mod_perl_traps', experimented ad
nauseum 
for 4 days now... this modperl newbie is missing something
important...

Lasting gratitude and a check in the mail for dinner on me to any of
you
who can offer any tips/help which unlock this riddle for me...

Cheers,
Ed Loehr

SYMPTOMS...
---
Spurious errors in my error_log with increasingly nasty consequences:

Can't upgrade that kind of scalar at XXX line NN...
Not a CODE reference at XXX line NN...
Modification of a read-only value attempted at XXX line NN...
Attempt to free unreferenced scalar.
Attempt to free unreferenced scalar during global destruction.
Attempt to free unreferenced scalar at XXX line NN...

Once upon a time, the server was fully functional even with these
occasional error messages (which is why I ignored them originally).
Now, they are frequent showstoppers, causing requests to fail
altogether with 500 errors and occasional segfaults...

I'm lumping these together because I suspect they are all related.
In any case, the severest of these at present seems to be the

Can't upgrade that kind of scalar at XXX line NN...

message, which causes the request to fail and seems to foul up that
child for the rest of its life.


FAILED REMEDIES...
--
- Turned off PerlFreshRestart
- Got rid of '$| = 1;'
- Got rid of #!/usr/bin/perl -w (!!)
- Check 'use diagnostics' output
- Got rid of string regex optimization flags ( $key =~
m/^xyz/o )
- Replaced use of 'apachectl restart' with
stop-sleep3-startssl;
- use Carp ();  local $SIG{__WARN__} = \&Carp::cluck;
- Changed global all instances of global 'my $var = 0' to
'use vars qw($var);  $var = 0;'
- Commented out Apache::Registry
(Most of these are just suggestions I found during my hunt...)

CONFIGURATION...

(detailed config dumps below)
mod_perl 1.21 (*NOT* Apache::StatINC)
mod_ssl 2.4.9
openssl 0.9.4
perl 5.005_03
DBI 1.13 (*NOT* using Apache::DBI)
DBD::Pg 0.92
Apache 1.3.9 (*VERY* lightly loaded)
Linux 2.2.12-20smp (RH 6.1), 1Gb RAM, RAID 5 (*lots* of free
mem)
Dual PII 450 cpus
Using modified TicketMaster scheme from Eagle book

OBSERVATIONS...
---
I'm convinced the code referenced by the error msgs (XXX line NN) is
almost at random; typically code that's worked flawlessly before
(sometimes my code, often not).  I suspect the line numbers in the
error msg may be screwed up.  #line did not clarify things.

If I rearrange my code, I have been able to make the error "move" to
another module (eg., from Exporter.pm to CGI.pm).  Smell like a stack
corruption problem?  Currently, the first unsuccessful statement is:

# ($r is the usual apache request object)
return ($retval,$msg)
unless $ticket{'ip'} eq
$r->connection->remote_ip;


In -X mode, once the server process hits one of these, it can no
longer
serve any modperl-generated page without a 500 error, occasionally
segfaulting in the process.

This also happens on both production and development server in
slightly
different manifestations (with slightly different httpd.conf files).

Other change factors that may or may not be related:  new firewall
rules,
increased number of open file handles (echo 8192 >
/proc/sys/file-max),
increased load, RAM upgrade, numerous modperl app src code changes,
added
more use of Time::HiRes to other modules, new SSL certificate, and
more...

Finally, totally commenting out my incarnation of the TicketMaster
scheme
from the Eagle book (cookie-based passworded sessions) *seems* to
remove
the problem, but it's a moving target so I'm not sure of that yet. 
Have
been unable to determine what it might be within TicketMaster that is
causing the problem.

NEXT STEPS...
-
Try removing Logger.pm from Apache::Ticket*
Whittle down until minimal set produces error?
Autoload troubles?
Find/try MacEachern's Apache::Leak?  Hunting XS errors?
Apache::Vmonitor?
Relying on $_ in foreach loops?
SSL Certificate differences?
Dreaded Last Step: setup debugger and chase ...

# /usr/local/apache_ssl/bin/httpd -l
Compiled-in modules:
  http_core.c
  mod_env.c
  mod_log_config.c
  mod_mime.c
  mod_negotiation.c
  mod_status.c
  mod_include.c
  mod_autoindex.c
  mod_dir.c
  mod_cgi.c
  mod_asis.c
  mod_imap.c
  mod_actions.c
  mod_userdir.c
  mod_alias.c
  mod_access.c
  mod_auth.c
  mod_setenvif.c
  mod_ssl.c
  mod_perl.c

# /usr/local/apache_ssl/bin/httpd -V
Server version: Apache/1.3.9 (Unix)
Server built:   Dec  9 1999 11:40

does ssl encrypt basic auth?

[Ed Loehr]

Is a basic authentication password, entered via a connection to an
https/SSL server, encrypted or plain text across the wire?

Re: does ssl encrypt basic auth?

[Ed Loehr]

[EMAIL PROTECTED] wrote:
> 
>  Ed Loehr wrote:
> >
> > Is a basic authentication password, entered via a connection to an
> > https/SSL server, encrypted or plain text across the wire?
> >
> Encrypted - but that question really doesn't belong here.
> It has nothing to do with modperl.

Yes, some of your fellow off-topic police have already served notice
privately.  My unstated context was that mod_perl authentication was
giving me fits, and in my effort to find an alternative, I (gasp)
posted off-topic.  I'm just glad you're watching.  :(

Building Apache/modperl for SCO OS 5.05

[ed hallda]

Has anyone had any luck building Apache on SCO Open Server 5 with mod_perl?
 We have been unsuccessful, and am hoping to find a solution.

r/

ed

$r->print delay?

[Ed Loehr]

Any ideas on why would this output statement takes 15-20 seconds to
send a 120kb page to a browser on the same host?

sub send_it {
my ($r, $data) = @_;

$| = 1;  # Don't buffer anything...send it asap...
$r->print( $data );
}   

modperl 1.21, apache/modssl 1.3.9-2.4.9...lightly loaded Linux (RH6.1)
Dual PIII 450Mhz with local netscape 4.7 client...

Re: $r->print delay?

[Ed Loehr]

Ken Williams wrote:
> 
> Are you sure it's waiting?  You might try debug timestamps before & after the
> $r->print().  You might also be interested in the send_fd() method if the data
> are in a file.

Fairly certain it's waiting there.  I cut my debug timestamps out for
ease on your eyes in my earlier post, but here's one output (of many
like it) when I had the print sandwiched...

Thu Feb 10 14:41:59.053 2000 [v1.3.7.1 2227:1 ed:1]  INFO : Sending
120453 bytes to client...
Thu Feb 10 14:42:14.463 2000 [v1.3.7.1 2227:1 ed:1]  INFO : Send of
120453 bytes completed.

Re send_fd(), it's all dynamically generated data, so that's not an
option...

Other clues?

> [EMAIL PROTECTED] (Ed Loehr) wrote:
> >Any ideas on why would this output statement takes 15-20 seconds to
> >send a 120kb page to a browser on the same host?
> >
> >$| = 1;  # Don't buffer anything...send it asap...
> >$r->print( $data );
> >
> >modperl 1.21, apache/modssl 1.3.9-2.4.9...lightly loaded Linux (RH6.1)
> >Dual PIII 450Mhz with local netscape 4.7 client...

Re: $r->print delay?

[Ed Loehr]

Greg Stark wrote:
> 
> Ed Loehr <[EMAIL PROTECTED]> writes:
> 
> > > [EMAIL PROTECTED] (Ed Loehr) wrote:
> > > >Any ideas on why would this output statement takes 15-20 seconds to
> > > >send a 120kb page to a browser on the same host?
> > > >
> > > >$| = 1;  # Don't buffer anything...send it asap...
> > > >$r->print( $data );
> 
> You don't say how many lines your 120kb of data is. If it's about 40
> characters per line average that's 30k calls to write (because you turned
> buffering off). Calls to write ought to be around 100us but if they were slow
> for some reason and took 500us then that would explain the 15s.

A number of the lines are 5-6K each.  Context is a rather large
html-based spreadsheet-like page.

> Additionally you're probably filling the kernel buffer and forcing a context
> switch several times. If the buffer is about 4k then there would be 3k context
> switches each about 10ms on linux, or about 30s of latency. There was a debate
> over the usefulness of the ProxyReceiveBuffer parameter, and even that isn't
> the same as this buffer, but it ought to be possible for Apache to setsockopt
> to ask for a larger buffer.
> 
> In short, don't set $|=1, it will only slow down this process, and investigate
> if there's any way to increase the size of the kernel buffer for the socket in
> Apache. Lots of people would be interested to know if you turn up anything
> there.

With buffering on or off, and max "segment" size of 900 bytes in any
one call to print() (or $r->print()), but doing 120kb worth of
printing in rapid succession, the smaller-but-still-large delay shows
up typically around 100kb into it.  The only way I was able to make
the large delays disappear so far is to sleep 1 every 50 prints or
so...but that's not really disappearing, now is it...

Experimentally, it appears this is simply too much data too quickly. 
I think I've seen $|=1 make a big difference with other non-local
NT/MSIE clients, even on these 120kb pages.  I've consistently been
able to reproduce this problem in both buffered and non-buffered mode
with linux netscape 4.7, both locally and remotely.

I'll look into the kernel buffer issue... :(

Cheers,
Ed Loehr

Can't upgrade that kind of scalar

[Ed Loehr]

Aside from gdb, any fishing tips on how to track this fatal problem
down?

Can't upgrade that kind of scalar at XXX line NN...

Happens intermittently, often on a call to one of these (maybe the
first access of $r?):

$r->server->server_hostname()
$r->connection->remote_ip()

I've tried turning off PerlFreshRestart, have _totally_ clean output
from 'use diagnostics', reviewed The Guide, 'perldoc perldiag', FAQ,
deja.com, swarthmore, removed /o, used Carp::cluck, handled global
vars with 'use vars qw(...)'...

Config:  apache 1.3.9, mod_perl 1.21, mod_ssl 2.4.9, openssl 0.9.4,
perl 5.005_03, DBI 1.13 (no Apache::DBI), DBD::Pg 0.92, Linux
2.2.12-20smp (RH 6.1)...

Re: $r->print delay?

[Ed Loehr]

"G.W. Haywood" wrote:
> 
> On Thu, 10 Feb 2000, Ed Loehr wrote:
> 
> > Fairly certain it's waiting there.  I cut my debug timestamps out for
> > ease on your eyes in my earlier post, but here's one output (of many
> > like it) when I had the print sandwiched...
> >
> > Thu Feb 10 14:41:59.053 2000 [v1.3.7.1 2227:1 ed:1]  INFO : Sending
> > 120453 bytes to client...
> > Thu Feb 10 14:42:14.463 2000 [v1.3.7.1 2227:1 ed:1]  INFO : Send of
> > 120453 bytes completed.
> >
> > Re send_fd(), it's all dynamically generated data, so that's not an
> > option...
> 
> So write a file...?

Duh.  In any event, send_fd() doesn't help.  Thanks anyway.

Cheers,
Ed Loehr

[RFI] URI escaping modules?

[Ed Loehr]

I just noticed that Apache::Util::escape_uri does not escape embedded '&'
characters as I'd expected.  What is the preferred module for escaping
'&', '?', etc. when embedded in strings?

Regards,
Ed Loehr

Re: Installation

[Ed Loehr]

> Annette wrote:
> 
> I have been trying to install mod_perl for the last couple of weeks and
> I still have not been successful. I am new to Linux and have installed
> RedHat 6. I used the Custom set-up and installed mod_perl during the
> installation. I entered the command 'perl -v' and it tells me that I
> have perl loaded but not mod_perl. Does anyone know what I have to do to
> enable mod_perl, tell if I have it enabled, or where I can read about
> the installation under RedHat 6. I have tried installing it using src
> files, followed the directions line by line and still nothing. Is this
> the right mailing list to ask this question? Where should I go if not?
> Apache is up and running just fine. Any input would be appreciated.

The essential can't-run-modperl-without-it guide:  

http://perl.apache.org/guide

Regards,
Ed Loehr

RE: loss of shared memory in parent httpd

[Ed Grimm]

I believe I have the answer...

The problem is that the parent httpd swaps, and any new children it
creates load the portion of memory that was swaped from swap, which does
not make it copy-on-write.  The really annoying thing - when memory gets
tight, the parent is the most likely httpd process to swap, because its
memory is 99% idle.  This issue aflicts Linux, Solaris, and a bunch of
other OSes.

The solution is mlockall(2), available under Linux, Solaris, and other
POSIX.1b compliant OSes.  I've not experimented with calling it from
perl, and I've not looked at Apache enough to consider patching it
there, but this system call, if your process is run as root, will
prevent any and all swapping of your process's memory.  If your process
is not run as root, it returns an error.


The reason turning off swap works is because it forces the memory from
the parent process that was swapped out to be swapped back in.  It will
not fix those processes that have been sired after the shared memory
loss, as of Linux 2.2.15 and Solaris 2.6.  (I have not checked since
then for behavior in this regard, nor have I checked on other OSes.)

Ed

On Thu, 14 Mar 2002, Bill Marrs wrote:

> >It's copy-on-write.  The swap is a write-to-disk.
> >There's no such thing as sharing memory between one process on disk(/swap)
> >and another in memory.
> 
> agreed.   What's interesting is that if I turn swap off and back on again, 
> the sharing is restored!  So, now I'm tempted to run a crontab every 30 
> minutes that  turns the swap off and on again, just to keep the httpds 
> shared.  No Apache restart required!
>
> Seems like a crazy thing to do, though.
> 
> >You'll also want to look into tuning your paging algorithm.
> 
> Yeah... I'll look into it.  If I had a way to tell the kernel to never swap 
> out any httpd process, that would be a great solution.  The kernel is 
> making a bad choice here.  By swapping, it triggers more memory usage 
> because sharing removed on the httpd process group (thus multiplied)...
> 
> I've got MaxClients down to 8 now and it's still happening.  I think my 
> best course of action may be a crontab swap flusher.
> 
> -bill

Re: Berkeley DB 4.0.14 not releasing lockers under mod_perl

[Ed Grimm]

Does shutting down apache free up your locks?

(As an aside, I'm not sure I'll ever get over undef being proper closing
of a database connection; it seems so synonomous to free([23]).  I
expect something like $db->db_close() or something.)

Ed

On Thu, 21 Mar 2002, Dan Wilga wrote:

> At 2:03 PM -0500 3/21/02, Aaron Ross wrote:
>>
>>>  I'm testing with the Perl script below, with the filename ending
>>>  ".mperl" (which, in my configuration, causes it to run as a mod_perl
>>>  registry script).
>>
>>  I would re-write it as a handler and see if Apache::Registry is partly
>>to blame.
> 
> I tried doing it as a handler, using the configuration below (and the 
> appropriate changes in the source) and the problem persists. So it 
> doesn't seem to be Registry's fault.
> 
> 
>  SetHandler perl-script
>  PerlHandler DanTest
> 
> 
>  source code 
> 
> #!/usr/bin/perl
> 
> package DanTest;
> 
> use strict;
> use BerkeleyDB qw( DB_CREATE DB_INIT_MPOOL DB_INIT_CDB );
> 
> my $dir='/home/httpd/some/path';
> 
> sub handler {
>   system( "rm $dir/__db* $dir/TESTdb" );
> 
>   foreach( 1..5 ) {
>   my $env = open_env($dir);
>   my %hash;
>   my $db = open_db( "TESTdb", \%hash, $env );
>   untie %hash;
>   undef $db;
>   undef $env;
>   }
>   print "HTTP/1.1 200\nContent-type: text/plain\n\n";
>   print `db_stat -c -h $dir`;
>   print "\n";
> }
> 
> sub open_env {
>   my $env = new BerkeleyDB::Env(
>   -Flags=>DB_INIT_MPOOL|DB_INIT_CDB|DB_CREATE,
>   -Home=> $_[0],
>   );
>   die "Could not create env: $! ".$BerkeleyDB::Error. "\n" if !$env;
>   return $env;
> }
> 
> sub open_db {
>   my( $file, $Rhash, $env ) = @_;
>   my $db_key = tie( %{$Rhash}, 'BerkeleyDB::Btree',
>   -Flags=>DB_CREATE,
>   -Filename=>$file,
>   -Env=>$env );
>   die "Can't open $file: $! ".$BerkeleyDB::Error."\n" if !$db_key;
>   return $db_key;
> }
> 
> 1;
> 
> 
> Dan Wilga [EMAIL PROTECTED]
> Web Technology Specialist http://www.mtholyoke.edu
> Mount Holyoke CollegeTel: 413-538-3027
> South Hadley, MA  01075"Seduced by the chocolate side of the Force"
> 

Re: 'Pinning' the root apache process in memory with mlockall

[Ed Grimm]

ow the limit, it'll be killed immediately after
> serving a single request (assuming that we the
> C<$CHECK_EVERY_N_REQUESTS> is set to one). This is a very bad
> situation which will eventually lead to a state where the system won't
> respond at all, as it'll be heavily engaged in swapping process.

Yes, this is why we want to lock the memory.

Ed

Re: Performace...

[Ed Grimm]

On Sun, 24 Mar 2002, Kee Hinckley wrote:
> At 2:27 PM -0500 3/23/02, Geoffrey Young wrote:
>>
>>you might be interested in Joshua Chamas' ongoing benchmark project:
>>
>>[EMAIL PROTECTED]">http://mathforum.org/epigone/modperl/sercrerdprou/[EMAIL PROTECTED]
>>http://www.chamas.com/bench/
>>
>>he has the results from a benchmark of Apache::Registry and plain 
>>handlers, as well as comparisons between HTML::Mason, Embperl, and 
>>other templating engines.
> 
> Although there are lots of qualifiers on those benchmarks, I consider 
> them rather dangerous anyway.  They are "Hello World" benchmarks, in 
> which startup time completely dominates the time. The things that 

That explains why Embperl did so poorly compared to PHP, yet when we
replaced our PHP pages with Embperl, our benchmarks using real user
queries, sending the same queries through the old and new pages, the new
pages showed a 50% performance boost.

Note: that gain was enough to saturate our test network.  Our purpose
for the benchmark was to determine if it was an improvement or not, not
to determine the exact improvement, so we don't really know what the
real gain was.  The same machines do several other tasks, and our
monitoring at the time of change was not very sophisticated, so we only
really know it was a big win.  Something on the order of 37 load issues
the week before the change, most of which were fairly obviously web
overload, and two the week after (those two being very obviously
associated with other services the boxes are running.)

Ed

Re: Apache::DBI or What ?

[Ed Grimm]

On Sun, 24 Mar 2002, Andrew Ho wrote:

>>What would be ideal is if the database would allow you to change the
>>user on the current connection.  I know PostgreSQL will allow this
>>using the command line interface psql tool (just do \connect
>> ), but I'm not sure if you can do this using DBI.
>>
>>Does anyone know if any datbases support this sort of thing?
> 
> This occurred to me in the case of Oracle (one of my co-workers was
> facing a very similar problem in the preliminary stages of one of his
> designs), and I actually had asked our DBAs about this (since the
> Oracle SQL*Plus also allows you to change users). As I suspected (from
> the similar "connect" terminology), our DBAs confirmed that Oracle
> just does a disconnect and reconnect under the hood. I would bet the
> psql client does the same thing.

First, I'll suggest that there are hopefully other areas you can look at
optimizing that will get you a bigger bang for your time - in my test
environment (old hardware), it takes 7.4 ms per
disconnect/reconnect/rebind and 4.8 ms per rebind.  Admittedly, I'm
dealing with LDAP instead of SQL, and I've no idea how they compare.

If the TCP connection were retained, this could still be a significant
win.  *Any* reduction in the connection overhead is an improvement.  If
there are a million connects per day, and this saves a milli-second per
connect (believable to me, as at least three packets don't need to be
sent - syn, syn ack, and fin.  My TCP's a bit fuzzy, but I think there's
a couple more, and there's also the mod_perl disconnect/reconnect
overhead), that's over 15 minutes of response time and about 560,000,000
bits of network bandwidth (assuming the DB is not on the same machine)
saved.  Admittedly, at 100Mb/s, that's only 6 seconds.

It may, in some cases, still be necessary to move access control from
the DB into ones application, so one can maintain a single connection
which never rebinds, but I think it's better to utilize the security in
the DB instead of coding ones own - more eyes have looked over it.
We're talking about a fairly small unit of time; it may very well be
better to throw money if you are near your performance limit.

Ed

Re: [announce] mod_perl-1.99_01

[Ed Grimm]

On Mon, 8 Apr 2002, Stas Bekman wrote:

> Ged Haywood wrote:
>> Compilations should be SILENT unless something goes wrong.
>
> The build process takes time, if you don't give an indication
> of what's going on users will try to do funky things. Since the
> build process is comprised of many small sub-processes you cannot
> really use something like completion bar.

As someone said, redirect the output to a temporary location.  But, add
to that one of those little | bars, which turns one position every time
another build step completes (each file compiled, each dependancy file
built, etc.).  However, in the case of an error, I would want the whole
thing available.  Possibly something along the lines of, the last build
step and all output from then on printed to stdout (or stderr), ended
with, "For the full build log, see /tmp/mod_perl.build.3942" or some
such.

> Also remember that mod_perl build prints very little,
> it's the compilation messages that generated most of the output.
> p.s. I don't recall seeing silent build processes at all.

The only ones I've seen went too far the other way.  I especially loved
the one which used a shell script, which started out with a dozen large
shell functions, then an 'exec >/dev/null 2>/dev/null', then a
half-dozen more large shell functions, and ending with 'main "$@"'.
When the shell script finished, its caller checked its exit code, and
reported 'done.' or 'failed.' as appropriate.  Admittedly, I wouldn't
have minded too much, except that I'd gotten the latter answer.

Ed

Re: mod perl load average too high

[Ed Grimm]

That looks like there's something that occasionally goes off and starts
spinning, given the low memory usage and the fact that some processes
using little cpu are also not swapped out.

I suspect that one of your pages has a potential infinite loop that's
being triggered.  Try and catch at what point the load suddenly starts
rising, and check what pages were accessed around that time.  They're
where you should start looking.

Note that you should probably focus on the access and error log lines
that correspond with processes that are using excessive amounts of cpu.

Ed

On Tue, 6 Aug 2002, Anthony E. wrote:

> I'm using apache 1.3.26 and mod_perl 1.27
> 
> My apache processes seem to be taking up more and more
> system resources as time goes on.
> 
> Can someone help me determine why my server load is
> going up?
> 
> When i first start apache, my "load average" is about
> .02, but after a couple of hours, it goes up to 4 or
> 5, and after a couple of days, has been as high as
> 155.
> 
> I have the following directives configured in
> httpd.conf:
> 
> MaxKeepAliveRequests 100
> MinSpareServers 5 
> MaxSpareServers 20
> StartServers 10
> MaxClients 200
> MaxRequestsPerChild 5000
> 
> Here is a snip of 'top' command:
>   6:28pm  up 46 days, 23:03,  2 users,  load average:
> 2.24, 2.20, 1.98
> 80 processes: 74 sleeping, 6 running, 0 zombie, 0
> stopped
> CPU0 states: 99.3% user,  0.2% system,  0.0% nice, 
> 0.0% idle
> CPU1 states: 100.0% user,  0.0% system,  0.0% nice, 
> 0.0% idle
> Mem:  1029896K av,  711884K used,  318012K free,  
> 0K shrd,   76464K buff
> Swap: 2048244K av,  152444K used, 1895800K free   
>   335796K cached
> 
>   PID USER PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM
>   TIME COMMAND
> 25893 nobody16   0 10188 9.9M  3104 R95.5  0.9
>  21:55 httpd
> 25899 nobody16   0  9448 9448  3104 R95.3  0.9
>  63:27 httpd
> 25883 nobody 9   0 10468  10M  3096 S 2.5  1.0
>   0:16 httpd
> 25895 nobody 9   0 10116 9.9M  3104 S 2.1  0.9
>   0:15 httpd
> 25894 nobody 9   0 10240  10M  3104 S 1.9  0.9
>   0:16 httpd
> 25898 nobody 9   0 10180 9.9M  3100 S 1.7  0.9
>   0:13 httpd
> 
> Also, I notice in my error_log i get this entry quite
> frequently:
> 26210 Apache::DBI new connect to
> 'news:1.2.3.4.5userpassAutoCommit=1PrintError=1'
> 
> What can i do to keep the server load low?
> 
> 
> =
> Anthony Ettinger
> [EMAIL PROTECTED]
> http://apwebdesign.com
> home: 415.504.8048
> mobile: 415.385.0146
> 
> __
> Do You Yahoo!?
> Yahoo! Health - Feel better, live better
> http://health.yahoo.com
> 

Re: PerlChildInitHandler doesn't work inside VirtualHost?

[Ed Grimm]

On Thu, 8 Aug 2002, Rick Myers wrote:

> On Aug 09, 2002 at 12:16:45 +1000, Cees Hek wrote:
>> Quoting Jason W May <[EMAIL PROTECTED]>:
>>> Running mod_perl 1.26 on Apache 1.3.24.
>>> 
>>> I've found that if I place my PerlChildInitHandler inside a VirtualHost
>>> block, it is never called.
>> 
>> It doesn't really make sense to put a PerlChildInitHandler
>> inside a VirtualHost directive.
> 
> Why? The Eagle book says this is a perfectly valid concept.

Well, for one thing, it would only call the handler if a request to that
virtual host was the first request for that child.  Assuming it works;
I'd think this would be a good canidate for a case that's never been
tested before, due to the fact that it would not call the handler if the
request that initiated the child was not to that virtual host...

It would fail to work in all cases if Apache does not recognize what
triggered the child until after child init.  Looking over pages 59
through 61, 72 and 73, this appears to me to be the case.  Yes, it does
explicitly say that it's ok in virtual host blocks, but it doesn't say
it works.

Ed

RE: Compiled-in but not recognized

[Ed Grimm]

On Sun, 11 Aug 2002, Colin wrote:

>> -Original Message-
>> From: Ged Haywood [mailto:[EMAIL PROTECTED]]
>> Sent: Sunday, August 11, 2002 6:02 PM
>> Subject: Re: Compiled-in but not recognized
>>
>>
>> Hi there,
>>
>> On Sun, 11 Aug 2002, Colin wrote:
>>
>>> I know this is a recurring problem but bear with me ...
>>
>> :)
>>
>>> httpd -l
>>> Compiled-in modules:
>>> http_core.c
>>> mod_so.c
>>> mod_perl.c
>>
>> pwd?

I think that Ged was suggesting you might have multiple httpd binaries
on your system, and was suggesting that you verify you're running the
binary you think you're running.

It's really annoying when you're trying to debug a program, and the
program you're running is not the one you're adding the debugging
statements to.  However, I suspect most of us have done it on occasion.

Ed
"How the #&@*! is it getting past all those debug statements without
hitting any?!?!" - Me

Re: Apache::Registry() and strict

[ed phillips]

Ron,

This is a greivous FAQ.  Please read the guide at
http://perl.apache.org/guide

You'll find much more than this question answered.

Ed



Ron Rademaker wrote:

> Hello,
>
> I'm just starting with mod_perl and I'm using Apache::Registry(). The
> second line after #!/usr/bin/perl -w is use strict;
> But somehow variables I use in the script are still defined if I execute
> the script again, in one of the script I said undef $foo at the
> end, but I don't think this is the way it should be done, but it did work.
> Anyone knows what could be causing this??
>
> Ron Rademaker
>
> PS. Please CC to me because I'm not subscribed to this mailinglist

enterprise mod_perl architectures

[Ed Park]

tensions that are generated when top management and VCs come
knocking with questions. In this way, it should dovetail nicely with the
mod_perl advocacy project.

I am not yet certain whether the best forum for this is this mailing list,
or whether I should try to create a private list of names for folks who are
interested. Relevant considerations include:
-The possible very off-topicness of pieces of the discussion.
-At some point, some of us may want opinions from other folks on sensitive
information (network diagrams, etc.) that Corporate won't allow us to show
to the outside world except under NDA; if all the folks on a list signed an
NDA, then we could speak freely all the time.
-At any rate, I'd like to publish any methodologies we use and put any
monitoring tools, performance benching tools, etc. into open-source. To that
end, I'll be creating a page that publishes any code we come up with and
summarizes our thoughts. I'd be happy to publish that page myself, but I
could also just add it as a page-- 'Enterprise mod_perl architectures'-- to
Matt's new site (modperl.sergeant.org).

So, I'd like to get folks' thoughts on this project. Again, I am staking out
very high ground on this project-- multimillion-dollar companies with
multimillion-dollar budgets. I'm doing this not because I'm disparaging
other companies, but because part of the reason behind doing this project is
to establish mod_perl's credibility as an enterprise web platform and to
describe some of the pitfalls and workarounds that allow mod_perl to scale
to that level. To that end, I'd like to get a list of interested parties. In
general, this should include the chief architects, CTOs, and/or senior
engineers at different shops using mod_perl. Some of those folks don't read
this list regularly, and in that case, I'd be happy to email them/call them
directly if people could just point them my way.

If any subset of folks are interested, I'd be more than happy to drive this
project forward. This is a project that really describes one of my core
responsibilities in my company right now, so I actually have a lot of time
and the resources to devote to this as part of my job.

Anyways, not to belabor the point-- I'd like y'alls input on this,
specifically:
1) What do folks thing about the project in general?
2) Should we keep it on this list, or should we create a separate mailing
list for interested parties, or should we do a combination of the two?
3) Is there anyone who'd like to volunteer virtual space to host this? e.g.
ftp, web, creating a mailing list, etc.

I am not yet interested in specifics about peoples' architectures; I think
that we need to frame the general discussion and create some infrastructure
before we go into that.

cheers,
Ed


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[OT]Re: mod_perl advocacy project resurrection

[ed phillips]

Aristotle from the Ars Rhetorica on money:

Money will not make you wise, but it will bring a wise man to your door.


Robin Berjon wrote:

> At 12:39 06/12/2000 -0800, brian moseley wrote:
> >> ActiveState has built an Perl/Python IDE out of Mozilla:
> >>  http://www.activestate.com/Products/Komodo/index.html
> >
> >too bad it's windows only :/
>
> That's bound to change. I think AS will release it on all platforms where
> Moz/Perl/Python run when it's finished. The current release is very
> unstable anyway.
>
> -- robin b.
> All paid jobs absorb and degrade the mind. -- Aristotle
>
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RE: eval statements in mod_perl

[Ed Park]

This was a problem that I had when I was first starting out with mod_perl;
i.e., it wouldn't work the first or second times through, and then it would
magically start working.

This was always caused for me by a syntax error in a library file. In your
case, it could be caused by a syntax error in a library file used somewhere
in your eval'd code. I highly suggest running
> perl -c 
on all of your library files to check them for valid syntax. If all of your
library files are in the same directory,
> perl -c *
will work as well.

I'm not certain for the technical reason for this, but I believe it has
something to do with the fact that syntax errors in the libraries are not in
and of themselves considered a fatal condition for loading libraries in
mod_perl, so the second or third time around the persistent mod_perl process
thinks that it has successfully loaded the library. Obviously, some
functions in that library won't work, but you won't know that unless you
actually use them. Someone else might be able to shed more light on this.

good luck,
Ed


-Original Message-
From: Gunther Birznieks [mailto:[EMAIL PROTECTED]]
Sent: Thursday, December 07, 2000 3:38 AM
To: Hill, David T - Belo Corporate; '[EMAIL PROTECTED]'
Subject: Re: eval statements in mod_perl


Without knowing your whole program, this could be a variety of logic
problems leading to this code. For example, perhaps $build{$nkey} is a
totally bogus value the first 2 times and hence your $evalcode is also
bogus the first two times -- and it's not a problem of eval at all!

This is unclear for the snippet.

At 10:52 AM 12/6/2000 -0600, Hill, David T - Belo Corporate wrote:
>Howdy,
> I am running mod_perl and have created a handler that serves all
the
>pages for our intranet.  In this handler I load perl programs from file
into
>a string and run eval on the string (not in a block).  The problem is that
>for any session the code doesn't work the first or second time, then it
>works fine.  Is this a caching issue or compile-time vs. run-time issues?
I
>am sure this is a simple fix.  What am I missing?
>
> Here is the nasty part (don't throw stones :)  So that we can
>develop, I put the eval in a loop that tries it until it returns true or
>runs 3 times.  I can't obviously leave it this way.  Any suggestions?  Here
>is the relevant chunk of code:
>
> #  Expect perl code.  Run an eval on the code and execute it.
> my $evalcode = "";
> my $line = "";
> open (EVALFILE, $build{"$nkey"});
> while ($line = ) {
> $evalcode .= $line;
> }
> my $evalresult = 0;
> my $counter=0;
>
>#
> #   Temporary measure to overcome caching issue, try
to
>#
> #   run the eval code 3 times to get a true return.
>#
>
>#
> until (($evalresult) || ($counter eq 3)) {
> $evalresult = eval $evalcode;
> $counter++;
> }
> $pageHash{"Retries"} = $counter if $counter > 1;
> $r->print($@) if $@;
> close (EVALFILE);
>
>I appreciate any and all constructive comments.
>
>-
>To unsubscribe, e-mail: [EMAIL PROTECTED]
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__
Gunther Birznieks ([EMAIL PROTECTED])
eXtropia - The Web Technology Company
http://www.extropia.com/


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RE: connect_cached, mod_perl && Oracle connection pooling

[Ed Park]

Hey--

I know that this is mad late, but this caught my eye, and it doesn't look
like anyone has responded since then.

For anyone else-- if you've even been in a situation where you've wanted to
create persistent DBI connections to multiple Oracle schemas, read on.

In short, here's the solution for that particular problem: there is a
completely undocumented function that is particular to DBD::Oracle that
allows you change your default schema within a particular database
connection.

See http://www.geocrawler.com/archives/3/183/2000/4/0/3652431/
In particular, if you look at the official DBD::Oracle install-test
directory (you can see it in /tmp/cpan/DBD-Oracle-1.03/t on titan), there's
a file called t/reauth.t. Here's a small chunk of code from that:
ok(0, ($dbh->selectrow_array("SELECT USER FROM DUAL"))[0] eq $uid1 );
ok(0, $dbh->func($dbuser_2, '', 'reauthenticate'));
ok(0, ($dbh->selectrow_array("SELECT USER FROM DUAL"))[0] eq $uid2 );

Early tests indicate that reauthentication is not a very expensive function
at all. We are currently testing this approach in development, and plan to
put it into production in the near future. If you use it, lemme know how it
works for you.

hope this helps,
Ed

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Saturday, September 23, 2000 6:09 PM
To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
Subject: connect_cached, mod_perl && Oracle connection pooling


DBI's connect_cached has been "new" for quite sometime now and has been
labeled with "exact behavior of this method is liable to change" since
it first showed up last year.

In November last year, Tim clarified his intentions for connect_cached
and suggested that DBI::ProxyServer be enhanced to provide a pool from
which connections can be checked in and out (or something like that).
Well, I'm now looking at possibly having a multiplicity of connect
strings in a mod_perl environment.  So Apache::DBI doesn't sound
suitable, I don't want every child to maintain connections nailed up for
every connect string (20 apache children * 20 connect strings = 400
nailed up connections, yowza!).  At any given time, the processing
happening in the mod_perl apache child process will only need one of
those connect strings.  Persistence connections are important just
because of the expense of setting up the Oracle connection.  So, I'm
wondering what folks think of non-persistent connections between
mod_perl and the dbiproxy but persistent connections with connect_cached
between dbiproxy and Oracle... does this make sense?  I was thinking
it'd be cool to be able to specify how many of each connections should
be maintained in the pool.  Is anybody doing this and care to share
their experiences with it?
thanks,
-Ian

--
Salon Internet  http://www.salon.com/
  Manager, Software and Systems "Livin' La Vida Unix!"
Ian Kallen <[EMAIL PROTECTED]> / AIM: iankallen / Fax: (415) 354-3326


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[OT] RE: Help needed with MAP expression

[Ed Park]

The point of this function is to right-align numbers in table-data cells and
keep everything else left-aligned. Note that this is what Excel does by
default (if you type in a number in Excel, it aligns to the right; if you
type in a string, it aligns to the left).

Technically, it should be use in the context of an arrayref that you are
transforming into an HTML table, e.g.:

use CGI qw(:all);
$_ = ['1','abc','2.34'];
print join "", map(/^[\.\d]+$/ ? td({-align=>'right'}, $_) : td($_), @$_);

A useful and clever piece of code, that. But the author probably should have
commented it. :)

cheers,
Ed


-Original Message-
From: bari [mailto:[EMAIL PROTECTED]]
Sent: Thursday, December 07, 2000 12:47 PM
To: [EMAIL PROTECTED]
Subject: Help needed with MAP expression


Hi there,
Can any one help me what this MAP function does...

 map(/^[\.\d]+$/ ? td({-align=>'right'}, $_) : td($_), @$_)

I am really confused by this one... your help would be appreciated..

Thank You,

- Bari

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[ANNOUNCE] new site: scaling mod_perl (+tool: mod_perl + DBD::Oracle)

[Ed Park]

The enterprise mod_perl architectures idea that I posted earlier has evolved
into a slightly modified idea: a 'scaling mod_perl' site:
http://www.lifespree.com/modperl.

The point of this site will be to talk about & synthesize techniques for
scaling, monitoring, and profiling large, complicated mod_perl
architectures.

So far, I've written up a basic scaling framework, and I've posted a
particular development profiling tool that we wrote to capture, time, and
explain all SQL select queries that occur on a particular page of a mod_perl
+ DBD::Oracle application:
-http://www.lifespree.com/modperl/explain_dbitracelog.pl
-http://www.lifespree.com/modperl/DBD-Oracle-1.06-perfhack.tar.gz

Currently, I'm soliciting thoughts and code on the following subjects in
particular:
1. Performance benchmarking code. In particular, I'm looking for tools that
can read in an apache log, play it back realtime (by looking at the time
between requests in the apache log), and simulate slow & simultaneous
connections. I've started writing my own, but it would be cool if something
else out there existed.
2. Caching techniques. I know that this is a topic that has been somewhat
beaten to a pulp on this list, but it keeps coming up, and I don't know of
any place where the current best thinking on the subject has been
synthesized. I haven't used any caching techniques yet myself, but I intend
to begin caching data at the mod_perl tier in the next version of my
application, so I have a very good incentive to synthesize and benchmark
various techniques. If folks could just send me pointers to various caching
modules and code, I'll test them in a uniform environment and let folks know
what I come up with. Or, if someone has already done all that work of
testing, I'd appreciate if you could point me to the results. I'd still like
to run my own tests, though.

If folks could point me towards resources/code for these topics (as well as
any other topics you think might be relevant to the site), please let me
know. I'm offering to do the legwork required to actually test, benchmark,
and synthesize all of this stuff, and publish it on the page.

I'm also still interested in actually talking with various folks. If anyone
who has been through some significant mod_perl scaling exercise would like
to chat for 15-30 minutes to swap war stories or tactical plans, I'd love to
talk with you; send me a private email.

cheers,
Ed


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RE: [ANNOUNCE] new site: scaling mod_perl will be movin to the Guide

[Ed Park]

I've gotten in touch with Stas, and the 'scaling mod_perl' site will
eventually be folded into the Guide. woohoo!

I'm going to spend several weeks fleshing it out and cleaning it up before
it goes in, though.

-Ed

-Original Message-
From: Perrin Harkins [mailto:[EMAIL PROTECTED]]
Sent: Friday, December 08, 2000 12:36 PM
To: Ed Park; [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Subject: Re: [ANNOUNCE] new site: scaling mod_perl (+tool: mod_perl +
DBD::Oracle)


> The enterprise mod_perl architectures idea that I posted earlier has
evolved
> into a slightly modified idea: a 'scaling mod_perl' site:
> http://www.lifespree.com/modperl.
>
> The point of this site will be to talk about & synthesize techniques for
> scaling, monitoring, and profiling large, complicated mod_perl
> architectures.

No offense, but the content you have here looks really well suited to be
part of the Guide.  It would fit nicely into the performance section.
Making it a separate site kind of fragments the documentation.

> So far, I've written up a basic scaling framework, and I've posted a
> particular development profiling tool that we wrote to capture, time, and
> explain all SQL select queries that occur on a particular page of a
mod_perl
> + DBD::Oracle application:
> -http://www.lifespree.com/modperl/explain_dbitracelog.pl
> -http://www.lifespree.com/modperl/DBD-Oracle-1.06-perfhack.tar.gz

Take a look at DBIx::Profile as well.

> 1. Performance benchmarking code. In particular, I'm looking for tools
that
> can read in an apache log, play it back realtime (by looking at the time
> between requests in the apache log), and simulate slow & simultaneous
> connections. I've started writing my own, but it would be cool if
something
> else out there existed.

The mod_backhand project was developing a tool like this called Daquiri.

> If folks could just send me pointers to various caching
> modules and code, I'll test them in a uniform environment and let folks
know
> what I come up with.

There are a bunch of discussions about this in the archives, including one
this week.  Joshua Chamas did some benchmarking on a dbm-based approach
recently.

- Perrin


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[JOB] mod_perl folks wanted in Boston - athenahealth.com

[Ed Park]

In the spirit of all of this talk about certification, demand for mod_perl
programmers, etc., I'd just like to say that I'm looking for programmers.

More to the point, I'm looking for kickass folks who just happen to know
mod_perl. If you know mod_perl very well, great, but generally speaking, I'm
looking for folks who are just kickass hackers, know that they are kickass
hackers, and are willing to do anything to drive a problem to extinction.

Experience with mod_perl, Linux, Oracle, Solaris, Java, XML/SOAP, MQ Series,
transaction brokers, systems administration, NT, DHTML, JavaScript, etc.
etc. are all Good Things. But basically, we're looking for folks who are
itching to prove themselves and have some sort of history that indicates
that they can do it.

As a backdrop: we just raised $30 million, and we were the top story in the
latest Red Herring VC Dealflow.
http://www.redherring.com/vc/2000/1206/vc-ltr-dealflow120600.html
As you have probably gathered by now from my posts about the Scaling
mod_perl page (http://www.lifespree.com/modperl/- soon to be folded into the
Guide), I'm currently starting up a scaling mod_perl project, and I have a
lot of money and stock options to burn on good people and interesting toys.

If you're interested, send me a private email & a resume and we'll talk.

Unfortunately, you sort of have to be in the Boston area (or willing to
move) to make this work.

cheers,
Ed


-
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Apache::Session benchmarks

[Ed Park]

FYI-- here are some Apache::Session benchmark results. As with all
benchmarks, this may not be applicable to you.

Basically, though, the results show that you really ought to use a database
to back your session stores if you run a high-volume site.

Benchmark: This benchmark measures the time taken to do a create/read for
1000 sessions. It does not destroy sessions, i.e. it assumes a user base
that browses around arbitrarily and then just leaves (i.e. does not log out,
and so session cleanup can't easily be done).

RESULTS: I tested the following configurations:

Apache::Session::MySQL - Dual-PIII-600/512MB/Linux 2.2.14SMP: Running both
the httpd and mysqld servers on this server. Average benchtime: 2.21 seconds
(consistent)

Apache::Session::Oracle - Ran the httpd on the dual-PIII-600/512MB/Linux
2.2.14SMP, running Oracle on a separate dual PIII-500/1G (RH Linux 6.2).
Average benchtime: 3.1 seconds (consistent). (ping time between the servers:
~3ms)

Apache::Session::File - Dual-PIII-600/512MB/Linux 2.2.14SMP: Ran 4 times.
First time: ~2.2s. Second time: ~5.0s. Third time: ~8.4s. Fourth time:
~12.2s.

Apache::Session::DB_File - Dual-PIII-600/512MB/Linux 2.2.14SMP: Ran 4 times.
First time: ~20.0s. Second time: ~20.8s. Third time: ~21.9s. Fourth time:
~23.2s.

The actual benchmarking code can be found at
http://www.lifespree.com/modperl/ (warning - the site is in a terrible state
right now, mostly a scratchpad for various techniques & benchmarks)

Question: does anyone know how to pre-specify the _session_id for the
session, rather than allowing Apache::Session to set it and read it? I saw
some posts about it a while back, but no code...

cheers,
Ed

RE: Article idea: mod_perl + JSP

[Ed Park]

I've been thinking about this quite a bit recently.

I agree with Gunther-- what is more important is not really the language
that you use, but the high-level application framework you have built for
yourself and how you use it. This is because most of the essential elements
of any framework can be duplicated in any reasonably powerful programming
language (mod_perl, java, tcl, even VBScript/VB to some extent).

That said, my own experience and benchmarking showed that mod_perl is the
best of these architectures for building extremely high-quality, reliable,
_complicated_ 3-tier Internet applications in which the prototyping and
release cycle are very highly compressed, because I can write the most
high-quality, high-speed code per unit time in Perl. By 3-tier apps, I mean
apps consisting of a browser, the app server (mod_perl), and an RDBMS.

Perl doesn't have much support in the way of n-tier apps, which is why I
find Nathan's question interesting, and why I have been thinking about it
recently. From some recent experiences with using SOAP to integrate with an
outside vendor, I believe that it is possible to create a best-of-breed
n-tier solution using Perl as the glue layer. For those of you who don't
know what SOAP is, it's essentially RPC over XML, and allows any app to talk
to any other app in a standard, XML-based format. Go to
http://www.soaplite.com for a very clean implementation of SOAP for Perl.

To continue-- there are a few reasons that you might want to use Java as a
component of a mod_perl app:
-There are sometimes pre-written components for Java that you'd like to use
because a vendor has written pre-specified hooks for Java. This could also
be the case in which you have to integrate with any legacy systems.
-Java has much better support for threading, and therefore in many cases
makes a much better server (the simple example for this is a chat server).
-Because of Java's threads, it can pool transactions resources (e.g.
databases) better, and may therefore be more efficient in places where
resources are tightly constrained, _especially_ if the database is queried
relatively infrequently.

For similar reasons, you might want to use a VB component in your
application, etc. SOAP makes that possible.

The point here is that I think that an awful lot of folks out there have
straitjacketed themselves into thinking that if there's a complicated
problem that needs to be solved, and there's a piece of that problem is best
done in Java, then we ought to write the whole thing in Java. What I'm
saying is that that's not necessarily true-- that it's actually possible to
write best-of-breed solutions by introducing a communications-layer
abstraction that enables you to build a clean n-tier architecture. CORBA
promised this, but was sufficently difficult to implement because it has not
(to my knowledge) gained very wide acceptance in the Perl community. Also,
the major ORBs (IONA, Visigenic) have largely overlooked creating Perl
bindings for theri apps. SOAP, however, makes distributed computing
extremely easy and _very_ clean, and I think that it could change the way
that people think about building complicated, high-quality applications in
an extremely compressed timecycle.

Using SOAP actually opens a number of other possibilities that don't require
thinking outside of mod_perl, too. For example, one of the big selling
points of Java is that it allows horizontal partitioning of classes on
different machines. Using SOAP, you can actually partition your _perl_ logic
so that different pieces run on different machines; or, you can write a
component in Perl that is subsequently called by a Java component.

OK, enough of my rambling...

cheers,
Ed

-Original Message-
From: Gunther Birznieks [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, December 12, 2000 11:42 PM
To: Chris Winters; Nathan Torkington
Cc: [EMAIL PROTECTED]
Subject: Re: Article idea: mod_perl + JSP


At 11:11 PM 12/12/2000 -0500, Chris Winters wrote:
>* Nathan Torkington ([EMAIL PROTECTED]) [001212 22:09]:
> >
> > Anyone run such an installation?  Anyone want to write about their
> > setup and experiences?
> >

There are projects where we use mod_perl handlers for stuff like
prototyping auth but then use servlets/JSPs for the app. But I believe
that's too shallow for what Nat wants.

We're a small shop of primarily fairly senior developers (at least several
years experience in the languages we like to use)... and we've actually
found that the Java web and the Perl web projects we've delivered on aren't
necessarily THAT far off in project delivery time than some Perl people
would have you believe.

Of course, we have a toolkit that we use to develop apps in both Perl and
Java which helps, but it's still interesting that business logic for people
experienced in the language of their choice isn't that bad in term

RE: Mod_perl tutorials

[Ed Park]

My two cents--

I really like the look of the take23 site as well, and I would be happy as a
clam if we could get modperl.org. I'd even be willing to chip in some
(money/time/effort) to see whether we could get modperl.org.

More than that, though, I think that I would really like to see take23 in
large measure replace the current perl.apache.org. I remember the first time
I looked at perl.apache.org, it was not at all clear to me that I could
build a fast database-backed web application using mod_perl. In contrast,
when you click on PHP from www.apache.org, you are taken directly to a site
that gives you the sense that there is a strong, vibrant community around
php. (BTW, I also like the look and feel of take23 significantly more than
php).

Anyways, those are my own biases. The final bias is that the advocacy site
should be hosted someplace _fast_; one of the reasons I initially avoided
PHP was that their _site_ was dog slow, and I associated that with PHP being
dog slow. Anyways, take23 is very fast for now.

cheers,
Ed

showing mod_perl execute time in access_log

[Ed Park]

quick, obvious trick:
This is a trivial modification of Doug's original Apache::TimeIt script that
allows you to very precisely show the Apache execute time of the page.

This is particularly useful if you want to know which pages of your site you
could optimize.

Here's a question, though: does anyone know an easy way of measuring how
long apache keeps a socket to the client open, assuming that KeepAlive has
been turned off? This is relevant because I want to know how long on average
it is taking clients to receive certain pages in my application. I know that
I can approximately calculate it from bandwidth, but I would expect the
actual number to vary wildly throughout a given day due to Internet
congestion.

cheers,
Ed

---
package AccessTimer;

# USAGE:
# Just put the following line into your .conf file:
#
# PerlFixupHandler AccessTimer
#
# and use a custom Apache log (this logging piece is not at all
mod_perl-based...
# see http://httpd.apache.org/docs/mod/mod_log_config.html)
#
# CustomLog /path/to/your/log "%h %l %u %t \"%r\" %>s %b %{ELAPSED}e"
#

use strict;
use Apache::Constants qw(:common);
use Time::HiRes qw(gettimeofday tv_interval);
use vars qw($begin);

sub handler {
my $r = shift;

$begin = [gettimeofday];
$r->push_handlers(PerlLogHandler=>\&log);

return OK;
}

sub log {
my $r = shift;

my $elapsed = tv_interval($begin);
$r->subprocess_env('ELAPSED' => "$elapsed");
return DECLINED;
}

1;

Re: is morning bug still relevant?

[ed phillips]

Please use the  MySQL modules list. Responses are timely.
;-)

ed

Subscribe: <mailto:[EMAIL PROTECTED]>




Vivek Khera wrote:

> >>>>> "SV" == Steven Vetzal <[EMAIL PROTECTED]> writes:
>
> SV> Greetings,
> >> to say "ping doesn't work in all cases" without qualifiying why and/or
> >> which drivers that applies to.
>
> SV> We've had to write our own ->ping method for the MySQL DBD
> SV> driver. Our developer tried to track down a maintainer for the
> SV> DBD::msql/mysql module to submit a diff, but to no avail.
>
> How old a version are you talking about?  In any case, according to
> CPAN, the DBD::mysql module is "owned" by
>
> Module id = DBD::mysql
> DESCRIPTION  Mysql Driver for DBI
> CPAN_USERID  JWIED (Jochen Wiedmann <[EMAIL PROTECTED]>)
> CPAN_VERSION 2.0414
> CPAN_FILEJ/JW/JWIED/Msql-Mysql-modules-1.2215.tar.gz
> DSLI_STATUS  RmcO (released,mailing-list,C,object-oriented)
> INST_FILE(not installed)
>
> and I *know* he's responsive to that email address at least as of a
> month or so ago, as we exchanged correspondence on another matter.
>
> --
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> Vivek Khera, Ph.D.Khera Communications, Inc.
> Internet: [EMAIL PROTECTED]   Rockville, MD   +1-240-453-8497
> AIM: vivekkhera Y!: vivek_khera   http://www.khera.org/~vivek/

RE: the edge of chaos

[Ed Park]

A few thoughts:

In analyzing a few spikes on our site in the last few days, a clear pattern
has emerged: the database spikes, and the database spikes induce a
corresponding spike on the mod_perl server about 2-6 minutes later(because
mod_perl requests start queuing up). This is exacerbated by the fact that as
the site slows down, folks start double and triple-clicking on links and
buttons, which of course just causes things to get much worse.

This has a few ramifications. If your pages are not homogeneous in database
usage (i.e., some pages are much heavier than others), then throttling by
number of connections or throttling based on webserver load doesn't help
that much. You need to throttle based on database server load. This requires
some sort of mechanism whereby the webserver can sample the load on the
database server and throttle accordingly. Currently, we just mount a common
NFS fileserver, sample every minute, and restart the webserver if db load is
too high, which works OK.

The best course of action, though, is to tune your database, homogenize your
pages, and buy a bigger box, which we're doing.

-Ed


-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Perrin Harkins
Sent: Thursday, January 04, 2001 6:38 PM
To: Justin
Cc: [EMAIL PROTECTED]
Subject: Re: the edge of chaos


Justin wrote:
> Thanks for the links! But. I wasnt sure what in the first link
> was useful for this problem, and, the vacuum bots discussion
> is really a different topic.
> I'm not talking of vacuum bot load. This is real world load.
>
> Practical experiments (ok - the live site :) convinced me that
> the well recommended modperl setup of fe/be suffer from failure
> and much wasted page production when load rises just a little
> above *maximum sustainable throughput* ..

The fact that mod_proxy doesn't disconnect from the backend server when
the client goes away is definitely a problem.  I remember some
discussion about this before but I don't think there was a solution for
it.

I think Vivek was correct in pointing out that your ultimate problem is
the fact that your system is not big enough for the load you're
getting.  If you can't upgrade your system to safely handle the load,
one approach is to send some people away when the server gets too busy
and provide decent service to the ones you do allow through.  You can
try lowering MaxClients on the proxy to help with this.  Then any
requests going over that limit will get queued by the OS and you'll
never see them if the person on the other end gets tired of waiting and
cancels.  It's tricky though, because you don't want a bunch of slow
clients to tie up all of your proxy processes.

It's easy to adapt the existing mod_perl throttling handlers to send a
short static "too busy" page when there are more than a certain number
of concurrent requests on the site.  Better to do this on the proxy side
though, so maybe mod_throttle could do it for you.

- Perrin

getting rid of multiple identical http requests (bad users double-clicking)

[Ed Park]

Does anyone out there have a clean, happy solution to the problem of users
jamming on links & buttons? Analyzing our access logs, it is clear that it's
relatively common for users to click 2,3,4+ times on a link if it doesn't
come up right away. This not good for the system for obvious reasons.

I can think of a few ways around this, but I was wondering if anyone else
had come up with anything. Here are the avenues I'm exploring:
1. Implementing JavaScript disabling on the client side so that links become
'click-once' links.
2. Implement an MD5 hash of the request and store it on the server (e.g. in
a MySQL server). When a new request comes in, check the MySQL server to see
whether it matches an existing request and disallow as necessary. There
might be some sort of timeout mechanism here, e.g. don't allow identical
requests within the span of the last 20 seconds.

Has anyone else thought about this?

cheers,
Ed

mod_perl + multiple Oracle schemas (was RE: Edmund Mergl)

[Ed Park]

John--

Another thing you may want to look into is just doing an
"alter session set current_schema" call at the top of your mod_perl page.
This is actually significantly faster than Tim's reauthenticate solution
(about 7X, according to my benchmarks).

It has become a supported feature as of Oracle 8i. For details on what I
did, see http://www.lifespree.com/modperl/ (which is still a total mess
right now-- I'll get around to cleaning it up sometime soon, I promise!)

cheers,
Ed

-Original Message-
From: John D Groenveld [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, January 10, 2001 5:10 PM
To: Edmund Mergl
Cc: [EMAIL PROTECTED]
Subject: Re: Edmund Mergl


Good to see you alive, well, and still coding Perl.

Months ago, about the time of the Perl conference so it may have slipped
under everyone's radar, Jeff Horn from U of Wisconsin sent you some patches
to Apache::DBI to use Oracle 8's re-authenticate function instead of
creating and caching a separate Oracle connection for each user. Did you
decide whether to incorporate them or to suggest another module name for
him to use? I wasn't  able to participate in the discussion at the time,
but I now have need for that functionality. I don't know if Jeff Horn is
still around, but I'll track him down if necessary and offer to work on it.

Also, I sent you a small patch to fix Apache::DBI warnings under Perl5.6.
I hate to be a pest, but I'm rolling out software where the installation
procedure requires the user to fetch Perl from Active State and Apache::DBI
from CPAN. I'd rather not ship my own version of yours or any CPAN module.

Thanks,
John
[EMAIL PROTECTED]

Re: Not even beginning - INSTALL HELP

[ed phillips]

If you are going to upgrade gcc for RH 7.0, I reccomend the
new source RPM for gcc to be found in the updates directory
on any redhat mirror site.  In fact, if you are sticking with RH
you should see about updating a number of things.

23,

Ed

"G.W. Haywood" wrote:

> Hi there,
>
> On Tue, 27 Feb 2001, A. Santillan Iturres wrote:
>
> > I have Apache 1.3.12 running on a RedHat 7.0 box with perl, v5.6.0 built for
> > i386-linux
> > I went to install mod_perl-1.25:
> > When I did:
> > perl Makefile.PL
> > I've got a:
> > Segmentation fault (core dumped)
>
> Did you build your Perl yourself?  Sounds like there's a problem with
> it.  Check out the mod_perl List archives for problems with gcc (the C
> compiler) that was shipped with RedHat 7.0.  You should probably get
> that replaced to start with.  (Or use Slackware - sorry:)
>
> 73,
> Ged.

Re: Varaible scope & memory under mod_perl

[ed phillips]

agh!

check the headers!


Steven Zhu wrote:

> How could I unsubscribe from [EMAIL PROTECTED] you so
> much.Steven.
>
>  -Original Message-
>

Re: Fast DB access

[ed phillips]

Matthew Kennedy wrote:

> I'm on several postgresql mailing lists and couldn't find a recent post
> from you complaining about 6.5.3 performance problems (not even by an
> archive search). Your benchmark is worthless until you try postgresql
> 7.1. There have been two major releases of postgresql since 6.5.x (ie.
> 7.0 and 7.1) and several minor ones over a total of 2-3 years. It's no
> secret that they have tremendous performance improvements over 6.5.x. So
> why did you benchmark 6.5.x?
>
> This is a good comparison of MySQL and PostgreSQL 7.0:
>
> "Open Source Databases: As The Tables Turn" --
> http://www.phpbuilder.com/columns/tim20001112.php3
>
> > We haven't tried this one. We are doing a project on mysql. Our preliminary 
>assessment is, it's a shocker. They justify not having commit and rollback!! Makes us 
>think whether they are even lower end than MS-Access.
>
> Again, checkout PostgreSQL 7.1 -- I believe "commit" and "rollback" (as
> you put it) are available. BTW, I would like to see that comment about
> MS-Access posted to pgsql-general... I dare ya. :P
>
> Matthew

You can scale any of these databases; Oracle, MySQL or PostgreSQL, but please research 
each one thoroughly and tune it properly before you do your benchmarking.  And, again, 
MySQL does support transactions now. Such chutzpah for them to have promoted an "atomic
operations" paradigm for so long without supporting transactions! But that discussion 
is moot now.

Please be advised that MySQL is threaded and must be tuned properly to handle many 
concurrent users on Linux. See the docs at http://www.mysql.com  The author of the PHP 
Builder column did not do his research, so his results for MySQL on Linux are way off.
Happily, though, even he got some decent results from PostgreSQL 7.0.

The kernel of wisdom here:  If you are going to use one of the Open Source databases, 
please use
the latest stable release (they improve quickly!) and please either hire someone with 
some expertise installing and administering, and tuning your database of choice on 
your platform of choice or do the research thoroughly yourself.

Ed

Re: Can AxKit be used as a Template Engine?

[ed phillips]

Michael Alan Dorman wrote:

> Matt Sergeant <[EMAIL PROTECTED]> writes:
> > It depends a *lot* on the type of content on your site. The above
> > www.dorado.com is brochureware, so it's not likely to need to be
> > re-styled for lighter browsers, or WebTV, or WAP, or... etc. So your
> > content (I'm guessing) is pure HTML, with Mason used as a fancy way
> > to do SSI, with Mason components for the title bars/menus, and so
> > on. (feel free to correct me if I'm wrong).
>
> It is more sophisticated than that, but you're basically right.  I do
> pull some tagset-like tricks for individual pages, so it's not totally
> pure HTML, but yeah, if we wanted to do WebTV we'd be fscked.
>
> > AxKit is just as capable of doing that sort of thing, but where it
> > really shines is to provide the same content in different ways,
> > because you can turn the XML based content into HTML, or WebTV HTML,
> > or WML, or PDF, etc.
>
> Ah---well a web site that does all of that isn't what first comes to
> mind when someone talkes about doing a "static site"---though now that
> you've explained further, I believe I understand exactly what you
> intended.
>
> > I talk about how the current Perl templating solutions (including
> > Mason) aren't suited to this kind of re-styling in my AxKit talk,
> > which I'm giving at the Perl conference, so go there and come see
> > the talk :-)
>
> Heh.  I agree entirely with this assesment---I can conceptualize a way
> to do it in Mason, but the processing overhead would be unfortunate,
> the amount of handwaving involved would be enormous, and it would
> probably be rather fragile.
>
> > So I take back that people wouldn't be using Mason for static
> > content. I was just trying to find a simple way to classify these
> > tools, and to some people (I'd say most people), Mason is more on
> > the dynamic content side of things, and AxKit is more on the static
> > content side of things, but both tools can be used for both types of
> > content.
> >
> > (I hate getting into these things - I wish I'd never brought up
> > Mason or EmbPerl)
>
> Well I will say that you made an excellent point that hadn't really
> occured to me---I use XML + XSL for a lot of stuff (the DTD I use for
> my resume is a deeply reworked version of one I believe you had posted
> at one time), but not web sites, in part because I'm not currently
> obligated to worry about "other devices"---so I don't exactly regret
> getting you to clarify things.
>
> Could I suggest that a better tagline would be that AxKit is superior
> when creating easily (re-)targetable sites with mostly static content?
> It might stave off more ignorant comments.
>
> Mike.

Matt,

I've also found your use of "static" to describe "transformable" or
"re-targetable"(unfortunate
word)" content to be confusing. This discussion helps clarify things, a
little. ;-)

Ed

Re: modperl/ASP and MVC design pattern

[ed phillips]

Francesco Pasqualini wrote:

> - Original Message -
> From: <[EMAIL PROTECTED]>
> To: "Francesco Pasqualini" <[EMAIL PROTECTED]>
> Cc: <[EMAIL PROTECTED]>
> Sent: Friday, April 20, 2001 8:11 PM
> Subject: Re: modperl/ASP and MVC design pattern
>
> >
> > You can (I have) accomplish this with mod_perl and HTML::Mason, Mason's
> > root level autohandler can play the role of the JSP model 2
> > "controller servlet": dispatching logic processing to Perl objects (er,
> > beans) and "forwarding" to a view (with the Mason $m->call_next or
> > $m->comp mechanisms).  I think the Apache::Dispatch stuff can also
> > perform this role (haven't played with it to say for certain).  I'll
> > qualify this by saying MVC is not a end in itself, there are a lot of
> > modern requirements for flexible branding, client form factor appropriate
> > and locale specific presentations that require the view/controller part to
> > be a lot smarter than the traditional concepts of MVC that I've seen call
> > for.  I've been referring to these needs in my own engineering discussions
> > as (yikes) MVC++  :)
>
> ... this is really interesting, can you point me to documentation about
> "MVC++"
> thanks
> Francesco

Francesco, I believe that Ian was joking, hence the yikes before the name, so
the above post is the documentation!

Ed

Re: modperl/ASP and MVC design pattern

[ed phillips]

[EMAIL PROTECTED] wrote:

> > Francesco, I believe that Ian was joking, hence the yikes before the name,
> > so  the above post is the documentation!
> >
> > Ed
> >
>
> .. so the best environment for the MVC++ design pattern is parrot/mod_parrot :)
> http://www.oreilly.com/news/parrotstory_0401.html
>
> Thanks
> Francesco
>

Exactly!

Wasn't Ian the one responsible for the mod_parrot MVC++ API?

ed

[ModPerl] missing POST args mystery

[Ed Loehr]

I'm stumped regarding some request object behavior in modperl, and after
searching the Guide, Google, and the list archives without success, I'm
hoping someone might offer another idea I could explore, or offer some
helpful diagnostic questions.

In a nutshell, my problem is that POSTed form key-value pairs are
intermittently not showing up in the request object inside my handler
subroutine.

I have a modperl-generated form:





...



...

...




Upon submission, the form data eventually flows to my PerlHandler... 

sub handler {
my $r = shift;
my @argsarray = ($r->method eq 'POST' ? $r->content() : $r->args());
...
}

Now, if I examine (print) the form values retrieved from the request
object upon entry into this handler (*after* I load them into $args),
'id' is not present at all.  I must be missing something trivially
obvious to some of you.

This is running Apache/1.3.19 (Unix) mod_perl/1.25 mod_ssl/2.8.3
OpenSSL/0.9.6a.

Regards,
Ed Loehr

Re: [ModPerl] missing POST args mystery

[Ed Loehr]

Ed Loehr wrote:
> 
> > >I'm stumped ...
> > >In a nutshell, my problem is that POSTed form key-value pairs are
> > >intermittently not showing up in the request object inside my handler
> > >subroutine.

As I was puzzling over this, I saw this error message in the logs...

(offline mode: enter name=value pairs on standard input)

A google search turned up a note about needing to have "$CGI::NO_DEBUG =
1" before calling CGI::Cookie->parse().  Adding that line of code before
my parse call seems to have fixed the problem.  At a glance, looks like
CGI.pm was strangely set to read from the command-line (default
$CGI::NO_DEBUG = 0), probably triggering a call of Apache's request->args
somewhere along the line.  How the default setting may have changed I
don't know, because I've been using CGI.pm for years without this
problem; I may have upgraded that package, picking up a change
accidentally.

Regards,
Ed Loehr