[Zope] Multithreading sessions

Dieter Maurer dieter at handshake.de
Wed May 28 14:27:01 EDT 2008

Jon Emmons wrote at 2008-5-23 08:58 -0400:
> ...
>I am running zope 2.9.4 and have observed that it will not simultaneously
>serve pages to my users.

Usually, it does.

I have seen database adapter packages (an old "psycopg" version, to be
precise) that forgot to release the GIL for some operations.
Then Zope freezes while these operations are executed.

A surprising report of a similar kind was: while Zope's embedded
profiler is in use, Zope effectively runs in single thread mode (such
that other threads do not distort the timing results).
Probably not your problem ... but who knows.

Further potential reasons (for almost surely not responsible for your
current problem:

  Expensive operations implemented in "C" (such as operations on huge

  Creating excessive amounts of objects (causing lots
  of generation 2 garbage collections which hold the GIL)


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