[ZODB-Dev] Re: Connection pool makes no sense

[Florent Guillaume]

> A little bit of history...
> We have zope as an application server for heavy loaded tech process. We
> have high peaks of load several times a day and my question is about how
> can we can avoid unused connections to remain in memory after peak is
> passed?
> Before ZODB-3.4.1 connection pool was fixed size of pool_size and that
> caused zope to block down while load peaks.
> ZODB-3.4.2 that is shipped with Zope-2.8.5 has connection pool that does
> not limit the opened connections, but tries to reduce the pool to the
> pool_size and this behavior is broken IMO.
> 
> Follow my idea...
> After peak load I have many (thousands of connections) that have cached
> up different objects including RDB  connections.

Huh are you sure? That would mean you have thousands of threads. Or 
hundreds or ZEO clients. Or hundreds of ZODB mountpoints.

By itself Zope never uses more than one connection per thread, and the 
number of thread is usually small.

If you see many RDB connections, then it's a RDB problem and not a ZODB 
problem. Something not releasing RDB connections quick enough, or 
leaking RDB connections.

Florent

-- 
Florent Guillaume, Nuxeo (Paris, France)   Director of R&D
+33 1 40 33 71 59   http://nuxeo.com   fg at nuxeo.com