[ZCM] [ZC] 1644/ 2 Reject "unacceptably slow performance"

[Collector: Zope Bugs, Features, and Patches ...]

Issue #1644 Update (Reject) "unacceptably slow performance"
 Status Rejected, Zope/bug medium
To followup, visit:
  http://collector.zope.org/Zope/1644

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= Reject - Entry #2 by ajung on Dec 30, 2004 5:57 am

 Status: Pending => Rejected

The collector is not the place for vague questions.
Use a related Zope mailing list instead.
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= Request - Entry #1 by dman13 on Dec 29, 2004 6:22 pm

The users of this Z4I (CMF) site report that the performance is unacceptable.  All data is stored in the ZODB.  Much of the presentation and business logic is custom code, however the Schema product is used extensively as is the core functionality of persistence, folders, and a filesystem-based skin.

Each page requires several (~3-8) seconds to render and return to the browser.  gkrellm reveals that this time is spent with the CPU at maximum load.  The operating system's virtual memory is not utilized at all.  Temporarily moving the site to a developer's workstation (3GHz P4 with 1G RAM) yields acceptable performance of around 1-2 seconds per page.

Using PTProfiler and the python profiler I identified and reduced many hotspots.  One such hotspot was retrieving Schema widgets for each of 20 objects displayed in a folder listing page.  For the folder listing I no longer use the Schema widgets but rather hope that the field's value will look decent in HTML.  All total I measured a marked improvement on the above-mentioned workstation.  The users have not reported any noticeable change on the production server.

At this point the profilers show that each operation (method, TALES expression) in rendering the folder listing consumes almost negligible processing time.

I realize this report is somewhat vague because I am unable to pinpoint the problem, however I was specifically asked to open a report regarding the matter.  

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