Which tickTime is honored? One in zoo.cfg or hbase.zookeeper.property.tickTime in hbase-site.xml?
My understanding now is, whichever tickTime is honored, session time can not be more than 20 times the value. I think this is whats happening on my cluster: My hbase.zookeeper.property.tickTime value is 6000 ms. However my timeout value is 300000 ms which is outside of 20 times tickTime. Hence ZooKeeper uses its syncLimit of 5, to generate 6000*5 = 30000 as timeout value for my RS sessions. I'll try increasing hbase.zookeeper.property.tickTime value in hbase-site.xml and will monitor my cluster over next few days. Thanks Kevin & Ted for your help. Ameya On Wed, Jun 5, 2013 at 2:45 PM, Ted Yu <[email protected]> wrote: > bq. I thought this property in hbase-site.xml takes care of that: > zookeeper.session.timeout > > From > > http://zookeeper.apache.org/doc/current/zookeeperProgrammers.html#ch_zkSessions > : > > 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. > The above means the shared zookeeper quorum may return timeout value > different from that of zookeeper.session.timeout > > Cheers > > On Wed, Jun 5, 2013 at 2:34 PM, Ameya Kantikar <[email protected]> wrote: > > > In zoo.cfg I have not setup this value explicitly. My zoo.cfg looks like: > > > > tickTime=2000 > > initLimit=10 > > syncLimit=5 > > > > We use common zoo keeper cluster for 2 of our HBase clusters. I'll try > > increasing this value from zoo.cfg. > > However is it possible to set this value cluster specific? > > I thought this property in hbase-site.xml takes care of that: > > zookeeper.session.timeout > > > > > > On Wed, Jun 5, 2013 at 1:49 PM, Kevin O'dell <[email protected] > > >wrote: > > > > > Ameya, > > > > > > What does your zoo.cfg say for your timeout value? > > > > > > > > > On Wed, Jun 5, 2013 at 4:47 PM, Ameya Kantikar <[email protected]> > > wrote: > > > > > > > Hi, > > > > > > > > We have heavy map reduce write jobs running against our cluster. > Every > > > once > > > > in a while, we see a region server going down. > > > > > > > > We are on : 0.94.2-cdh4.2.0, r > > > > > > > > We have done some tuning for heavy map reduce jobs, and have > increased > > > > scanner timeouts, lease timeouts, have also tuned memstore as > follows: > > > > > > > > hbase.hregion.memstore.block.multiplier: 4 > > > > hbase.hregion.memstore.flush.size: 134217728 > > > > hbase.hstore.blockingStoreFiles: 100 > > > > > > > > So now, we are still facing issues. Looking at the logs it looks like > > due > > > > to zoo keeper timeout. We have tuned zookeeper settings as follows on > > > > hbase-sie.xml: > > > > > > > > zookeeper.session.timeout: 300000 > > > > hbase.zookeeper.property.tickTime: 6000 > > > > > > > > > > > > The actual log looks like: > > > > > > > > > > > > 2013-06-05 11:46:40,405 WARN org.apache.hadoop.ipc.HBaseServer: > > > > (responseTooSlow): > > > > {"processingtimems":13468,"call":"next(6723331143689528698, 1000), > rpc > > > > version=1, client version=29, methodsFingerPrint=54742778","client":" > > > > 10.20.73.65:41721 > > > > > > > > > > > > > > ","starttimems":1370432786933,"queuetimems":1,"class":"HRegionServer","responsesize":39611416,"method":"next"} > > > > > > > > 2013-06-05 11:46:54,988 INFO org.apache.hadoop.io.compress.CodecPool: > > Got > > > > brand-new decompressor [.snappy] > > > > > > > > 2013-06-05 11:48:03,017 WARN org.apache.hadoop.hdfs.DFSClient: > > > > DFSOutputStream ResponseProcessor exception for block > > > > BP-53741567-10.20.73.56-1351630463427:blk_9026156240355850298_8775246 > > > > java.io.EOFException: Premature EOF: no length prefix available > > > > at > > > > > > > > > > > > > > org.apache.hadoop.hdfs.protocol.HdfsProtoUtil.vintPrefixed(HdfsProtoUtil.java:162) > > > > at > > > > > > > > > > > > > > org.apache.hadoop.hdfs.protocol.datatransfer.PipelineAck.readFields(PipelineAck.java:95) > > > > at > > > > > > > > > > > > > > org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer$ResponseProcessor.run(DFSOutputStream.java:656) > > > > > > > > 2013-06-05 11:48:03,020 WARN org.apache.hadoop.hbase.util.Sleeper: > *We > > > > slept 48686ms instead of 3000ms*, this is likely due to a long > garbage > > > > collecting pause and it's usually bad, see > > > > http://hbase.apache.org/book.html#trouble.rs.runtime.zkexpired > > > > > > > > 2013-06-05 11:48:03,094 FATAL > > > > org.apache.hadoop.hbase.regionserver.HRegionServer: ABORTING region > > > server > > > > smartdeals-hbase14-snc1.snc1,60020,1370373396890: Unhandled > exception: > > > > org.apache.hadoop.hbase.YouAreDeadException: Server REPORT rejected; > > > > currently processing smartdeals-hbase14-snc1.snc1,60020,1370373396890 > > as > > > > dead server > > > > > > > > (Not sure why it says 3000ms when we have timeout at 300000ms) > > > > > > > > We have done some GC tuning as well. Wondering what I can tune from > > > making > > > > RS going down? Any ideas? > > > > This is batch heavy cluster, and we care less about read latency. We > > can > > > > increase RAM bit more but not much (Already RS has 20GB memory) > > > > > > > > Thanks in advance. > > > > > > > > Ameya > > > > > > > > > > > > > > > > -- > > > Kevin O'Dell > > > Systems Engineer, Cloudera > > > > > >
