Re: [Zope] SQLSession vs FSSession for ultra-high scalability andspeed.
On Sun, 21 May 2000, chas wrote: Hi Folks, Sorry if this has been asked before, but can anybody advise on FSSession vs SQLSession for: a) Speed. b) Scalability. FSSession does not use ZODB to store data, but stores session pickles directly on the harddisk. It will also update session info only if there are modifications to the session object. Given OS file caching I would not be supprised if FSSession is faster than any RDBMs based solution. Also note that if you have to support many writes on the Session objects, a filesystem provides a nice map from users -- files, which then utilizes the 'high concurrency' provided by the FS. OTO an RDBMS maybe a more reliable datastore than the filesystem with better consistency, recovery tools etc etc. Also check whether SQLSession caches info. It used to hit the RDBMs for every variable access which was very prohibitive for us, but Anthony mentioned that he was changing that. Since performance is going to be a major issue in your design I suggest you run a small bechmark to test relative performance. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] FSSession newbie problem
Hi Marcello
On Wed, 7 Jun 2000, Marcello Lupo wrote:
and macically i obtain the same error.
this is the code i used:
dtml-call FSSession
dtml-unless "FSSession.has_key('cart')"
dtml-call "FSSession.set('cart',{})"
/dtml-unless
dtml-call "FSSession['carrello'].update(REQUEST.form)"
Shouldn't the above be:
dtml-call "FSSession['cart'].update(REQUEST.form)"
Pavlos
___
Zope maillist - [EMAIL PROTECTED]
http://lists.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
http://lists.zope.org/mailman/listinfo/zope-announce
http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] Re: FSSession newbie problem
On Fri, 9 Jun 2000, Marcello Lupo wrote:
dtml-var "FSSession('carrello')"br It prints out "None"
I supose you mean ...FSSession['carrello'] ..
The FSSession is in the same folder of my two methods, may be this a
problem?
No it should not
one.
Probably the second method point to a different session file than the
first.
I also have dtml-call FSSession in my standard html header and I never
had problems. I will try a few tests when I return. Please keep me posted
if you continue having troubles.
Pavlos
___
Zope maillist - [EMAIL PROTECTED]
http://lists.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
http://lists.zope.org/mailman/listinfo/zope-announce
http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] Re: FSSession newbie problem
On Fri, 9 Jun 2000, Marcello Lupo wrote:
1) Is necessary to call FSSession in every document of the site or is
sufficient on the first page (home page of the e-com for example)?
Becouse i noticed (obviously) that every time it open a file the HD.
And i think this is a problem because every time it initialize a new
session passing the new cookie to the Browser (i think).
Yes it is neccessary beacuse HTTP is stateless. It will only start a new
session if FSSession cannot find a valid UID either through a cookie or a
FORM or as part of te URL
2) How may i change the value of an element in a dictionary contained in
FSSession?
Example: I have the object 'carrello' as in the examples before that
contain a dictionary passed to it from the form.
I store the quantity of the item ordered in the value
'quantita_prodotto' in the object 'carrello'.
If a user add another piece of that item i need to update the
'quantita_prodotto' summing to it the new item.
I think this is possible but i ignore the syntax to do this.
As you descripe in your example carrello is a dictinory. So one way is to
make quantitita_prodotto a list and append to it. Something like
untested
dtml-if "FSSession['carrillo'].has_key('quantita_prodotto')"
dtml-call
"FSSession['carrillo']['quatita_prodotto'].append(REQUEST.form['quatita_prodotto'])"
dtml-else
!-- need to fake the = sign which cannot be used in DTML expr--
dtml-call "FSSession['carrillo'].update({'quatita_prodotto':[]})"
/dtml-if
plus some more logic to check if the variables are empty/correct etc ..
Pavlos
___
Zope maillist - [EMAIL PROTECTED]
http://lists.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
http://lists.zope.org/mailman/listinfo/zope-announce
http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] Re: FSSession newbie problem
On Fri, 9 Jun 2000, Hung Jung Lu wrote: Pavlos: this is the part that is confusing to newbies. FSSession can be made in such a way that this initial call can be avoided. HappySession works that You are right. There is no real need for the initial call. It was initially designed like this because I inherited directly from UserDict and I was lazy to override every call to check whether FSSession was initialized or not. Also and more important I wanted to be compatible with SQLSession so the migrating users from one to the other will do so without needing to change much of the code. The initial call is useful if you need to pass parameters, like noCookie or _force_new_session etc etc. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] ZODB/FSSession TransactionError
On Wed, 28 Jun 2000, Dieter Maurer wrote: That's strange, because Python usually indicates EOF by returning an empty string and not by raising EOFError. cPickle returns EOFError which is confusing since the Python docs state that only input and raw_input return this exception. The problem is actually deeper than I previously thought. I am still not sure whether it is FSSession that is causing it or Zope's transaction manager. I will spend more time on it tomorrow. In any case if you delete the offending FSSession file on the filesystem and restart Zope it should be fine for now. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] Howto engineer a scientific paper system
On Thu, 29 Jun 2000, [EMAIL PROTECTED] wrote: Thank you for the comments and links for latex and docbook. Going the latex path seems to me worthwhile - but on another day ;-) , I have already done some setup in zope that I would like to build on. What I did not find about LaTeX was a screenshot (isn't it Having used latex for a long time I would like to point out that if you are planing to to write many papers for conferences/publications Latex has some very helpful tools. For one many scientific journals provide Latex style files so you don't need to worry about formating. Also (and IMO the most important) are the pain in the ... bib contents. There are very nice bib databases for Latex and latex (or bibtex) can produce bibliography contents in the formats required by most journals. Check also Lynx which is a minimal (last i checked) wysiwig environment for Latex. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] basic FSSession question
On Mon, 3 Jul 2000, Leichtman, David J wrote: overwrites the other data, implying that it's the same SessionUID. I thought that calling dtml-call FSSession from a different machine, would then create a new session with the SessionUID stored on that machine. How, then, do I get multiple sessions? Yes it will create a new Session. I have not received such a complain in the past so please check your setup carefully. If the problem persists can you send me a description of your setup so I can try to recreate it? There seems to be a severe lack of documentation for FSSession. Can you email me more specific suggestions as to where the docs need improvement? Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] Re: FSSession buglette
On Fri, 7 Jul 2000, Paul Gresham wrote: Hi, Yep, I'm definitely running 0-4-0, I think the fact that I did something naughty caused the rename (and therefore the commit) to fail, when it expected to work. An exception in the commit then caused Zope to stop all commits. What is worrying is that someone much more naughty than I am, may just do something similar on our live system (Once this goes live) Paul When I was testing FSSession-0-4-0 before release I created all sorts of weird situations and at least I got the impression that even under those situations FSSession would behave ok. I suppose I could make it foolproof by trying to serialize the contents everytime someone makes changes. This would guarantee that no exception will be raised during commit, but as I understand it it should be ok if an exception is raised during the first phase of commit (ie during tpc_begin). Zope should remain in a consistent state and the transaction machinery should clean up things ok, if something bad happens during the first phase of commit. It is only if an exception is raised in the second phase of commit that Zope refuses to carry on more transactions. In any case please send me your setup that creates such a problem with FSSession0.4.0 so I can look into it. If you want to restrict the kind of objects that your users will store in FSSession you could swap _dump and -load for the equivalent marshal ones. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] FSSession used in Python???
On Fri, 7 Jul 2000, Dan Narkiewicz wrote:
inside my own python written Zope product... Any help would be.. well...
helpful..
I am not sure if it is a good idea to use a Product in the manner you
describe but in any case:
--- a class definition ---
def FStest(self):
"""fssession test"""
self.a = FSSession() error appears here
FSSession needs to be initialized with a cookie name, (whatever one wants
to call the cookie that will store the session id).
self.a=FSSession('Danssession')
Still it might not work if FSSession cannot access REQUEST etc. Let me
know.
Pavlos
___
Zope maillist - [EMAIL PROTECTED]
http://lists.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
http://lists.zope.org/mailman/listinfo/zope-announce
http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] FSSession - don't call FSSession twice!
On Tue, 1 Aug 2000 [EMAIL PROTECTED] wrote: Zope has encountered an error while publishing this resource. Error Type: OSError Error Value: [Errno 2] No such file or directory from the title) that I called FSSession twice. Line 193 appears to rename a .tmp file and I'd guess that by calling it twice my second attempt fails as the file has already been renamed. Obviously this Hope this is of some use Ian Ian Thanks for the report and the excellent analysis. Unfortunately I did not consider the case of calling FSSession twice. During the last couple of days I had a few suggestions (Brian and Dieter) on improving FSSession so a new version soon. Thanks Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] REPOST: README.txt Tab
On Fri, 4 Aug 2000 [EMAIL PROTECTED] wrote: I'll re-ask the question: How do I get the README tab to appear in a product? What do I need to do? Its been a while but I think what you say is essentially correct. If there is a README.txt it would be displayed assuming your product was initialized correctly. Also make sure you delete the product from the product management screen and restart Zope. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] FSSession problems...
On Mon, 28 Aug 2000, Curtis Maloney wrote: /dtml-if This was aparently working fine for quite some time (about a month of public usage), until last week. We have examined logs, and seen that one person accidentaly used the system under someone elses ReturnerID, and then rectified their mistake. If he did rectify the mistake then that should not have resulted in a problem. In any case the problem should have been isolated to that user only. Could it be that the cookie is cached somewhere? I am not familiar with the underlying pricinciples of the apache Proxy directives. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
[Zope] [ANN] FSSession-0-4-2
Hello Zopistas FSSession 0-4-2 is available at: http://www.zope.org/Members/gaaros/FSSession FSSession 0-4-2 corrects a bug on Windows platforms where os.rename fails if the renamed file already exists. This version has also been tested under many "unusual" situations (calling FSSession twice, two users having the same SessionUID) and it seems to be very robust. Regards Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] HappySession
On Fri, 1 Sep 2000, Dieter Maurer wrote: I can tell you, that FSSession has the same problem, at least the version before the current one (announced some days ago). FSSession has no longer such problem. However you might still loose data if you access the same SessionUID from many frames. I don't thing there is a general solution to the problem without involving read locks which will slow down the whole Zope site. Or raising ConflictErrors which for frame usage like the case you mention will occur very often. The same problem will occur whether you store the Session info in an RDBMs or not. For instance: Thread A reads Session1 Thread B reads Session1 Thread A modifies Session1 and commits Thread B modifies Session1 and commits. This creates a conflict and the solution I have chosen is to keep the last to commit. In general we can achieve very high write rates because there is a natural isolation among requests, one thread per SessionUID. Problems will occur if multiple concurrent requests try to access the same SessionUID. This could occur in situations that employ frames but (at least in our case) most of the time the Session info is required only in one frame. In any case I have tested the latest version of FSSession against multiple frames accessing the same SessionUID and I do not get TransactionErrors. Actually there is a slightly better way but it will involve a lot of complicated programming so I won't even mention it ... :-) Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] OSError along with FSSession...
On Wed, 6 Sep 2000, Chien-Pin Wang wrote: Dear Zope Users: I have upgraded to FSSession 0.4.2 lately and occasionally run into the same problem several times. Each time it costs me a zope down. I do really need some help... Zope complains an error type "OSError" and throws the error value saying [Errno 21] Is a directory: '/usr/local/zope/var/FSSession/' occasionally since a recent upgrade of FSSession product to 0.4.2. I have managed to reproduce the error by setting SessionUID to an empty string before calling FSSession. Check for situations where you clear the REQUEST variables before calling FSSession. In the meantime I will add some checks on the input values of SessionUID. I will probably release a fixed version during the weekend if not sooner. Pavlos ___ Zope maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Re: [Zope-dev] ExtensionClass and __radd__()?
On Wed, 5 Jul 2000, Greg Ward wrote: Well, it's a nice theory. It doesn't explain why '__add__()' works for ExtensionClass while '__radd__()' does not; perhaps ExtensionClass implements that much of Python's class semantics, but doesn't go as far as '__radd__()'. A quick note which you probably already know: grep add ExtensionClass.c gives: static PyObject *py__add__, *py__sub__, *py__mul__, *py__div__, INIT_PY_NAME(__add__); BINOP(add,Add) FILLENTRY(nm-nb, add, add, METH_VARARGS, "Add to another"); FILLENTRY(sm-sq, concat, add, METH_VARARGS, SET_SPECIAL(add,add); subclass_add(PyObject *self, PyObject *v) UNLESS(m=subclass_getspecial(self,py__add__)) return NULL; AsCMethod(m)-meth==(PyCFunction)add_by_name ASSIGN(m,AsCMethod(m)-type-tp_as_number-nb_add(self,v)); (binaryfunc)subclass_add, /*nb_add*/ (binaryfunc)subclass_add, /*sq_concat*/ return; /* we added a reference; don't delete now */ whereas grep radd ExtensionClass.c returns nothing Pavlos ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )
