Zope 2.9.0 We are seeing spontaneous restarts of Zope with no indication in any of the standard Zope logs. Looking at the ZEO log indicates that the restarts of Zope are due to a lost connection between Zope & ZEO but with no other information. The logging level is set at the distribution default (INFO). The restarts are a huge problem because session variables are not persistent and so all of the user state they contain is lost on restart. In our statful implementation, this is a major problem. I want to adjust the configuration so that the Zope/ZEO connection is stable. In our configuration, Zope and ZEO are linked via localhost on a distinguished port. I've Googled about looking for some infomation about tuning the ZEO/Zope interface, but have found little real information. Some additional log detail would be helpful. We are running a fairly vanilla setup, excerpted below: <<zope.conf>> # ZEO client storage: # <zodb_db main> mount-point / # ZODB cache, in number of objects cache-size 5000 <zeoclient> server localhost:8301 storage 1 var $INSTANCE/var # ZEO client cache, in bytes cache-size 20MB # Uncomment to have a persistent disk cache client group1-zeo </zeoclient> </zodb_db> <<zeo.conf>> <zeo> address localhost:8301 read-only false invalidation-queue-size 100 pid-filename $INSTANCE/var/ZEO.pid # monitor-address PORT # transaction-timeout SECONDS </zeo> <runner> program $INSTANCE/bin/runzeo socket-name $INSTANCE/etc/zeo.zdsock daemon true forever false backoff-limit 10 exit-codes 0, 2 directory $INSTANCE default-to-interactive true # user zope python /usr/bin/python2.4 zdrun /usr/local/src/zope/Zope2.9/lib64/python/zdaemon/zdrun.py # This logfile should match the one in the zeo.conf file. # It is used by zdctl's logtail command, zdrun/zdctl doesn't write it. logfile $INSTANCE/log/zeo.log </runner> It's not clear what changes will lead to a more stable connection because it is not clear what's triggering the problem. Any advice would be appreciated. Presumably the shotgun approach would work -- increase the cache sizes, lengthen the invalidation-queue-size, and increase the backoff-limit but it would be nice to have some guidance. 5~