[Zope] Zope number of threads

Dieter Maurer dieter@handshake.de
Tue, 24 Dec 2002 12:20:23 +0100


Thierry Florac wrote at 2002-12-23 09:52 +0100:
 > I didn't found any answer to this probably simple question : what's the
 > best way to define a "good" number of threads for Zope ?
 > Is the default number defined in z2.py (4) the best for every situation,
 > or does this number have to be increased when working with sites with a
 > high volume of transactions ??
When you are concerned with throughput (and you do most work inside
Zope and not in external processes, such as external relational databases),
you use a small number of threads.

When most of the work is done outside of Zope or you want to optimize
response time, a higher thread number is adequate.

Each thread requires a ZODB database connection. The Zope code currently
limits the number of such connections to 7.
When you want to increase Zope's thread number beyond 7, you should also
increase the connection number. Zope will then need more memory (for its
ZODB caches).


Dieter