If you are running ZEO (Zope Enterprise Objects), the storage server keeps a log similar to event.log, in STORAGE_HOME/log/zeo.log . The log level is configured in STORAGE_HOME/etc/zeo.conf .
Here you can see when long ZODB [pack]? operations have completed, and also when zeo cache is flipping too often due to being too small.
With Zope versions older than 2.7, this is called something else.
correction -- Wed, 31 Aug 2005 10:08:31 -0700 reply
The ZEO (Zope Enterprise Objects) cache flip happens on the client side. You find them in the Zope event log (normally log/event.log), not in log/zeo.log. A typical one looks like:
"2005-06-22T07:50:59 INFO(0) ZEC:/path/to/your/instance/var/cmain-client1-1.zec flipping cache files. new current = 1"