On Wed, Sep 14, 2011 at 3:23 AM, Laxman <[email protected]> wrote: > Our customers are recently complaining about zookeeper client session > timeouts. > > When analyzed its found that timeouts are due to heavy GC activity on > Clients. > > So, they wanted to increase the session timeouts to 3 minutes which requires > the ticktime to be increased to atleast 9 seconds. >
I assume you've talked to them about fixing their gc issue at some point? Rather than band-aiding it? :-) I don't think you need to touch the tickTime here. See "maxSessionTimeout" here: http://zookeeper.apache.org/doc/r3.3.3/zookeeperAdmin.html#sc_advancedConfiguration (hbase has a similar issue, that's why we added this feature initially). Really though they should fix the gc issue - setting the session timeout higher means that their sessions will be expiring only after a much longer time. Any reliance on this - such as for leader election fail-over, will now take much more time. In your example it would take 3 minutes for the other clients to notice when a client with the particular session has become unavailable. Perhaps it doesn't matter in your use case, but you are now likely to get complains about ZK not being responsive. ;-) Regards, Patrick
