[Zope] Memory management problems

[Chris McDonough]

Many things could be going on here.  I don't know of any outstanding
memory leaks in Zope itself.  There may be one in Plone or another
3rd-party product you're using.  Or you may have created one within your
own code.  Tracking down memory leaks is hard and it's not clear to even
tell you where to start.  Best advice is to use binary exclusion in the
template that serves up the page (comment out half of it, serve it up,
see if that leaks, if so, divide in half again, and so on).  Once you've
tracked it down, remediation is another thing altogether, however.

On Tue, 2005-04-19 at 20:27, Peter Millar wrote:
> I have a serious memory problem.  And would like to hear from anyone who
> has large image files being served up to a large number of simultaneous
> user base.
> 
> I am running plone 2.0, zope 2.7.3, python 2.3.3, on windows 2003 server
> with 1.5 GB RAM.
> 
> I have a 1MB image.  I have created a little script to copy and paste
> this image.  To do it 50 times takes 6 minutes and uses up 300 MB of
> RAM.  If I then view the folder that contains all the images and start
> viewing the zpt that serves a single image it takes 40 seconds to a
> minute 20 and chews up approx 2-5MB.  If I then get a few other machines
> to request the same image at the same time, it takes 20seconds for the
> first machine, 40 seconds for the next machine and 1 min for the next
> machine and another 20 MB of ram has been chewed up.  Each time I go to
> serve a page my CPU usage jumps to 50% for the minute or so.
> 
> After doing this over and over for a few minutes sees my machine has no
> RAM left.  The only way to recover is to restart zope.
> 
> My question after all of this is how in the world can anyone seriously
> use plone/zope in a real world scenario with potentially millions of
> users accessing a site viewing content if you have to restart your zope
> service every minute.
> 
> I have spent the past two days looking at all sorts of cacheing ideas,
> session ideas etc.
> 
> Is there some magic that I need to apply for this to work like any
> number of web image viewers.  Or is it a case of throwing 100GB of Ram
> at the machine.
> 
> ____________________________________________ 
> Peter Millar 
> 
> 
> 
> _______________________________________________
> Zope maillist  -  Zope at zope.org
> http://mail.zope.org/mailman/listinfo/zope
> **   No cross posts or HTML encoding!  **
> (Related lists - 
>  http://mail.zope.org/mailman/listinfo/zope-announce
>  http://mail.zope.org/mailman/listinfo/zope-dev )
>