[Zope] RE: Zope memory leak (Progess being made!)

Jean-Francois.Doyon@CCRS.NRCan.gc.ca Jean-Francois.Doyon@CCRS.NRCan.gc.ca
Tue, 21 Jan 2003 15:10:29 -0500


Hello,

OK, I've made some progress thanks to LeakFinder!

Looks like the problem in my case is definitely the
DateTime.DateTime.DateTime class reference count.

I need some help understanding this stuff though, cuz we're going a bit
beyond my current python knowledge :)

First of all, some strange things I noticed:

- Since I installed leak finder, the refcount for said class grows much more
rapidly (presumably because it's more accurate?) and reaches much higher
levels than I have ever witnessed using the regular "top refcount" from the
Debug section of the Control Panel.

- The Top Refcount section of the debug panel now shows the same refcount as
the LeakFinder does, instead of the kind of values I had gotten used to
seeing previous to installing LeakFinder.

- More interestingly though, since I installed LeakFinder, the leak has
gotten worse! Memory usage grows to unmanageable levels in a matter of 2 or
3 days now, instead of a week or 2 as before. Is this normal? Is this a
symptom of what might be causing the problem? In my limited knowledge of
such python wizardry, I'm gussing it's because references that used to get
"lost" no longer aren't ... does that make sense?

I'm going to apply the "patch" very soon now. I tested this on my staging
server, which is an exact copy, and didn't see anything weird in the report,
so I'll try it on the live site.

The main thing is, I don't think I've written a single line of code that
uses that class anywhere. I have no Python Script or Products that do
anything with that class, except maybe through sub-classing of other objects
that may use it. The only usage of dates I do specifically (not within CMF
internal workings) is for displaying only.

More to come ...

Thanks for everyone's patience and help in this matter!

Cheers,
J.F.

-----Original Message-----
From: Dieter Maurer [mailto:dieter@handshake.de]
Sent: Friday, January 17, 2003 4:11 PM
To: Jean-Francois.Doyon@CCRS.NRCan.gc.ca
Cc: cmuldrow@fredericksburg.com; zope@zope.org
Subject: Re: [Zope] RE: Zope memory leak


Jean-Francois.Doyon@CCRS.NRCan.gc.ca wrote at 2003-1-17 11:47 -0500:
 > I do have dtml-var's with Dates in them in there too (DublinCore dates),
 > maybe there's a problem with some of the methods or objects?
You should use Shane's "LeakFinder" to find leaks caused by Zope objects.

 > I'm not sure what IOBuckets are FOR, I mean Input/Output, but not sure
where
 > they're used ... Maybe figuring that out could help?
There are an elementary structure to implement BTrees.
They are use in the catalog, among others.



Dieter