Hello, I am using hbase 0.90.0 with hadoop-append. h/w ( Dell 1950, 2 CPU, 6 GB RAM)
I had 9 Region Servers crash (out of 30) in a span of 30 minutes during a heavy reads. It looks like a GC, ZooKeeper Connection Timeout thingy to me. I did all recommended configuration from the Hbase wiki... Any other suggestions? 2011-02-03T09:43:07.890-0800: 70693.632: [GC 70693.632: [ParNew (promotion failed): 5555K->5540K(5568K), 0.0280950 secs]70693.660: [CMS2011-02-03T09:43:16.864-0800: 70702.606: [CMS-concurrent-mark: 12.549/69.323 secs] [Times: user=11.90 sys=1.26, real=69.31 secs] 2011-02-03T09:53:35.165-0800: 71320.785: [GC 71320.785: [ParNew (promotion failed): 5568K->5568K(5568K), 0.4384530 secs]71321.224: [CMS2011-02-03T09:53:45.111-0800: 71330.731: [CMS-concurrent-mark: 17.511/51.564 secs] [Times: user=38.72 sys=5.67, real=51.60 secs] 2011-02-03T09:43:07.890-0800: 70693.632: [GC 70693.632: [ParNew (promotion failed): 5555K->5540K(5568K), 0.0280950 secs]70693.660: [CMS2011-02-03T09:43:16.864-0800: 70702.606: [CMS-concurrent-mark: 12.549/69.323 secs] [Times: user=11.90 sys=1.26, real=69.31 secs] The following is the log entry in region Server 2011-02-03 10:37:43,946 INFO org.apache.zookeeper.ClientCnxn: Client session timed out, have not heard from server in 47172ms for sessionid 0x12db9f722421ce3, closing socket connection and attempting reconnect 2011-02-03 10:37:43,947 INFO org.apache.zookeeper.ClientCnxn: Client session timed out, have not heard from server in 48159ms for sessionid 0x22db9f722501d93, closing socket connection and attempting reconnect 2011-02-03 10:37:44,401 INFO org.apache.zookeeper.ClientCnxn: Opening socket connection to server XXXXXXXXXXXXXXXX 2011-02-03 10:37:44,402 INFO org.apache.zookeeper.ClientCnxn: Socket connection established to XXXXXXXXX, initiating session 2011-02-03 10:37:44,709 INFO org.apache.zookeeper.ClientCnxn: Opening socket connection to server XXXXXXXXXXXXXXX 2011-02-03 10:37:44,709 INFO org.apache.zookeeper.ClientCnxn: Socket connection established to XXXXXXXXXXXXXXXXXXXXX, initiating session 2011-02-03 10:37:44,767 DEBUG org.apache.hadoop.hbase.io.hfile.LruBlockCache: Block cache LRU eviction started; Attempting to free 81.93 MB of total=696.25 MB 2011-02-03 10:37:44,784 DEBUG org.apache.hadoop.hbase.io.hfile.LruBlockCache: Block cache LRU eviction completed; freed=81.94 MB, total=614.81 MB, single=379.98 MB, multi=309.77 MB, memory=0 KB 2011-02-03 10:37:45,205 INFO org.apache.zookeeper.ClientCnxn: Unable to reconnect to ZooKeeper service, session 0x22db9f722501d93 has expired, closing socket connection 2011-02-03 10:37:45,206 INFO org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation: This client just lost it's session with ZooKeeper, trying to reconnect. 2011-02-03 10:37:45,453 INFO org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation: Trying to reconnect to zookeeper 2011-02-03 10:37:45,206 INFO org.apache.zookeeper.ClientCnxn: Unable to reconnect to ZooKeeper service, session 0x12db9f722421ce3 has expired, closing socket connection gionserver:60020-0x22db9f722501d93 regionserver:60020-0x22db9f722501d93 received expired from ZooKeeper, aborting org.apache.zookeeper.KeeperException$SessionExpiredException: KeeperErrorCode = Session expired at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.connectionEvent(ZooKeeperWatcher.java:328) at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.process(ZooKeeperWatcher.java:246) at org.apache.zookeeper.ClientCnxn$EventThread.processEvent(ClientCnxn.java:530) at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:506) handled exception: org.apache.hadoop.hbase.YouAreDeadException: Server REPORT rejected; currently processing XXXXXXXXXXXX,60020,1296684296172 as dead server org.apache.hadoop.hbase.YouAreDeadException: org.apache.hadoop.hbase.YouAreDeadException: Server REPORT rejected; currently processing XXXXXXXXXXXX,60020,1296684296172 as dead server at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.apache.hadoop.ipc.RemoteException.instantiateException(RemoteException.java:96) at org.apache.hadoop.ipc.RemoteException.unwrapRemoteException(RemoteException.java:80) at org.apache.hadoop.hbase.regionserver.HRegionServer.tryRegionServerReport(HRegionServer.java:729) at org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:586) at java.lang.Thread.run(Thread.java:619) 2011-02-03T09:53:35.165-0800: 71320.785: [GC 71320.785: [ParNew (promotion failed): 5568K->5568K(5568K), 0.4384530 secs]71321.224: [CMS2011-02-03T09:53:45.111-0800: 71330.731: [CMS-concurrent-mark: 17.511/51.564 secs] [Times: user=38.72 sys=5.67, real=51.60 secs] Thanks, Charan