ID:               14254
 Updated by:       [EMAIL PROTECTED]
 Reported By:      [EMAIL PROTECTED]
 Status:           Open
 Bug Type:         Informix related
 Operating System: Solaris 8
 PHP Version:      4.0.6
 New Comment:

Referring to Bug #14254.

I can give some background clues which might help in resolving the
intermittent SQLCODE=-439 error faster.
I support the php scripts for the same server which Cedric supports.
We
have noted that our client has increased their volume of data and
traffic to the site dramatically since their intranet's inception over
a
year ago.

They're still using php3 (we're trying to convince them to pay us to
convert their scripts to php4, but presently can't guarantee this
would
resolve the problem since it's still being reported by others using
php4).

The effect seen is a refusal to connect to informix, caused by a peak
in
traffic. It's not something which is easily duplicated in a test
environment, and is a mercurial problem in that as soon as it occurs,
it
often dissappears again as suddenly. We've seen it occur regularly for
up to 40 minutes and then go away for several days.

Recently the complaint has been that some scripts simply return an
empty
page. On investigation this week I discovered these scripts were
building massive arrays while remaining connected to informix, and
apparently exceeding maximum script memory. It happens within 4-5
seconds so can't be the result of a timeout.

I suspect this is giving rise to accumulated garbage somewhere or
leaving locks in the database and has a serious effect on subsequent
attempts to connect to informix, which (sometimes) return SQLCODE=-439
error codes from ifx_connect().

We've tried using both ifx_connect and ifx_pconnect for the scripts,
but
this makes no apparent difference, just as increasing connection
limits
has failed to.

I've since optimised some of the offending scripts and this seems to
alleviate the problem in the short-term, but a huge overhaul of the
methods used is overdue but cannot be done so quickly, given the
complexity of the intranet.

We'd like a resolution of the problem as soon as possible, even with
scripts timing out or exceeding memory limits. I see you've recently
improved the memory threading, and wonder if this could finally crack
this long-standing problem?
Alan Frostick


Previous Comments:
------------------------------------------------------------------------

[2001-11-28 07:26:16] [EMAIL PROTECTED]

a short script would not reproduce the conditions for recreating the
failure.

It happens when we have a lot of load and this with big scripts using
lots of memory and sometimes timing out.
If the timeout comes from the db connection being lost or vice versa is
hard to say

If we could isolate where in the php ifx interface callback functions
are used we would be a step further in solving this.


------------------------------------------------------------------------

[2001-11-27 12:57:34] [EMAIL PROTECTED]

Can you please add a short PHP script with which you can
reproduce this ? Also, please try PHP 4.1.0 (to be released
very soon now) as it has some improvements to the threading
which might actually fix this problem.

(it was mentioned as one possibility in that mail you 
pointed to in the archives)

I don't have informix installed or any knowledge how to
set it up either so you need to help us in this.

And I don't have much time to spend on this either so please
be patient.

--Jani



------------------------------------------------------------------------

[2001-11-27 12:36:25] [EMAIL PROTECTED]

Similarly to Bugs 13459 and 8267 we do get error 439.

on php 3.0.18 and 4.0.6

http://marc.theaimsgroup.com/?l=php-dev&m=97812975300057&w=2



we do have support from ifx.

they are prepared to help us

here qote from ifx support 

----

I have received this case and I have looked through the case history.
The

situation appears to be as follows.



Your network traffic has increased and that in turn brought about
more

timeout situations where an ESQL/C callback was used by your
application (or

by PHP). The -439 error indicates that unauthorized calls are included
in

that callback function.



There are two ways to avoid getting the errors.



        1. Tweak the system to increase performance to the point where the

timeouts do not occur.

        2. Fix the callback function code.



Since you have indicated that you will not attempt number 1 we are left
with

number 2. Number 2 is the responsibility of the person that wrote the

callback function, be that you or PHP. 



The only way that Informix can fix the problem is if the -439 is being
given

in error. At this time there is no indication that the -439 error is
not

correct but it is still a possibility. Unfortunately we cannot know
whether

or not the -439 error is erroneous or not until we know exactly how
the

callback function is being set up. So the next thing that must happen
is

that I get a small test case showing setting up a correct callback
function

that fails with this error. 



If you are writing the callback functions then we need to get PHP out
of the

picture and you need to provide me a very small ESQL/C test case that
gives

the same error.



If the callback functions are contained in PHP then the only other
option is

to pursue an answer through Apache tech support and let them contact me
when

and if they find that the -439 is not correct. In that case they will
be

providing the test case. If PHP cannot be removed from the picture then
you

need to open a case with Apache as soon as possible. Given the nature
of

Apache this might not be a viable option and you may instead want to
look at

the PHP source yourself.

-- end quote

--- begin quote

Both the -439 and the -25588 errors are occuring because of timeouts.
Odds

are that they are simply different symptoms of the same underlying
problem

and which error you get depends on timing of internal events.



If you want to focus on performance tuning I can pass the case back to
an

engines engineer. This will only be brushing the problem under the
carpet,

however. If your application is not doing callbacks correctly then it
will

give this error any time that activity gets too high.



Does your application provide the callback function or is that all
built

into PHP?



-- end quote





so now we have the chance to get rid of this annoying bug. I cnnot
possibly plunge into the phpsourcecode to get the info the guy from ifx
needs.



If your are interested to get this thing sorted out this is the
chance





------------------------------------------------------------------------


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