I am working on a solution that has a very high number of users and a
significant amount of traffic. Using a zeo configuration we have been running
into a few bottle necks while trying to improve our load testing results. The
problem we see is if that put our Zeo Configuration under load that Zope does
not close the connections and the application server ends up running out of
connections for Apache to connect to. The connections once opened idle
indefinitely. (Apache is running on a dedicated server different from our Zeo
instances). We are using RR between 2 vm instances using 10 zeo clients per vm
to distribute load. The bottleneck is occurring on the Apache server because
it's keeping TCP connections in time_wait status.
We have completed load tests on both Windows 2003 and 2008. In 2003 we were
able to adjust the registry so the OS would terminate connections after 15
seconds of idle, however in 2008 the minimum is 30 seconds. In the upper
levels of testing the OS runs out of TCP connections because it can't close
them fast enough and it begins to fail requests. Ideally we don't want to
close connections forcibly via the tcp stack because Zope keeps them open.
We'd hope that Zope would manage this clean up gracefully.
One option we are considering is using IIS7.5 and ARR as a replacement load
balancing/rewrite method. This could allow us to check health of destinations
prior to forwarding a request. It may also give us more control over closing
connections at the OS level.
One other detail we think might be the issue is that Zope is not initiating the
close connection event.
Does anyone have any experience or knowledge they can lend to help out?
Windows 2003/2008 server
MS SQL 2005
sqlalchemy version is 0.6.5
Jimmy Small (mallaice)
This electronic message is intended only for the use of the addressee(s) named
above and may contain legally privileged and/or confidential information. If
you are not the intended recipient of this message, you are notified that any
dissemination, distribution or copying of this message is strictly prohibited.
If you received this message in error, please immediately notify the sender by
telephone and delete the original message.
Zope maillist - Zope@zope.org
** No cross posts or HTML encoding! **
(Related lists -