We already faced this issue and found out the issue to be long GC pauses itself on either client side or server side. Regards, Piyush
On Sat, May 6, 2017 at 6:10 PM, Shawn Heisey <apa...@elyograg.org> wrote: > On 5/3/2017 7:32 AM, Satya Marivada wrote: > > I see below exceptions in my logs sometimes. What could be causing it? > > > > org.apache.zookeeper.KeeperException$SessionExpiredException: > > Based on my limited research, this would tend to indicate that the > heartbeats ZK uses to detect when sessions have gone inactive are not > occurring in a timely fashion. > > Common causes seem to be: > > JVM Garbage collections. These can cause the entire JVM to pause for an > extended period of time, and this time may exceed the configured timeouts. > > Excess client connections to ZK. ZK limits the number of connections > from each client address, with the idea of preventing denial of service > attacks. If a client is misbehaving, it may make more connections than > it should. You can try increasing the limit in the ZK config, but if > this is the reason for the exception, then something's probably wrong, > and you may be just hiding the real problem. > > Although we might have bugs causing the second situation, the first > situation seems more likely. > > Thanks, > Shawn > >
