The actual session timeout is negotiated btw the client and server, there is both a min and a max enforced by the server.
See this section on session details: http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkSessions "One of the parameters to the ZooKeeper client library call to create a ZooKeeper session is the session timeout in milliseconds. The client sends a requested timeout, the server responds with the timeout that it can give the client. The current implementation requires that the timeout be a minimum of 2 times the tickTime (as set in the server configuration) and a maximum of 20 times the tickTime. The ZooKeeper client API allows access to the negotiated timeout." You're seeing the default (20*ticktime, which is typically 2 sec, so 40sec max) See here: (maxSessionTimeout) http://zookeeper.apache.org/doc/r3.3.3/zookeeperAdmin.html#sc_advancedConfiguration btw, setting a 10min timeout will probably cause you problems down the road - as things that depend on ephemeral nodes (e.g. leader failover) will take too long to be effective. (typically) Patrick On Wed, Oct 19, 2011 at 8:48 AM, Martin Serrano <[email protected]> wrote: > I'm seeing something a bit weird. In our environment we've upped the session > timeout to 10 minutes. I see that the client connections successfully > negotiate the 10 minute timeout. However I've seen a case where the client > session gets timed out in 40s if it is unable to ever initiate the session. > Is there a separate timeout somewhere? > > Thanks, > Martin > > Log excerpts below (unfortunately the server-side logs are not available): > > 2011-10-18 21:38:59,218 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread()-0] - Opening socket connection to server > localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:38:59,220 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Session 0x0 for server > null, unexpected error, closing socket connection and attempting reconnect > 2011-10-18 21:39:00,181 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Opening socket > connection to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:00,184 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:00,241 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session establishment > complete on server localhost/127.0.0.1:16015, sessionid = 0x13319d4a8c3000c, > negotiated timeout = 600000 > 2011-10-18 21:39:00,326 INFO ZooKeeper [main] - Initiating client > connection, connectString=localhost:16015 sessionTimeout=600000 > watcher=com.attivio.global.AieZooKeeper@45490eb5 > 2011-10-18 21:39:00,329 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread()-0] - Opening socket connection to server > localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:00,329 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Session 0x0 for server > null, unexpected error, closing socket connection and attempting reconnect > 2011-10-18 21:39:00,665 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Opening socket > connection to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:00,666 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:00,670 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session establishment > complete on server localhost/127.0.0.1:16015, sessionid = 0x13319d4a8c3000d, > negotiated timeout = 600000 > 2011-10-18 21:39:02,125 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to read additional > data from server sessionid 0x13319d4a8c3000d, likely server has closed > socket, closing socket connection and attempting reconnect > 2011-10-18 21:39:02,125 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional > data from server sessionid 0x13319d4a8c3000c, likely server has closed > socket, closing socket connection and attempting reconnect > 2011-10-18 21:39:02,295 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:02,295 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:02,873 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:02,873 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:03,676 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:03,677 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:03,678 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d > for server localhost/127.0.0.1:16015, unexpected error, closing socket > connection and attempting reconnect > 2011-10-18 21:39:04,027 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:04,027 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:04,416 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection > to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:04,417 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:04,417 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional > data from server sessionid 0x13319d4a8c3000c, likely server has closed > socket, closing socket connection and attempting reconnect > 2011-10-18 21:39:04,705 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:04,705 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:05,447 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:05,448 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:05,449 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to read additional > data from server sessionid 0x13319d4a8c3000d, likely server has closed > socket, closing socket connection and attempting reconnect > > Lots more of those, then: > > 2011-10-18 21:39:39,387 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection > to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:39,388 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:39,388 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional > data from server sessionid 0x13319d4a8c3000c, likely server has closed > socket, closing socket connection and attempting reconnect > 2011-10-18 21:39:39,592 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:39,592 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:39,735 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection > to server localhost/0:0:0:0:0:0:0:1:16015 > 2011-10-18 21:39:39,735 WARN ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c > for server null, unexpected error, closing socket connection and attempting > reconnect > 2011-10-18 21:39:41,400 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection > to server localhost/127.0.0.1:16015 > 2011-10-18 21:39:41,401 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection > established to localhost/127.0.0.1:16015, initiating session > 2011-10-18 21:39:41,402 INFO ClientCnxn > [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to reconnect to > ZooKeeper service, session 0x13319d4a8c3000d has expired, closing socket > connection >
