Jean-Daniel Cryans created HBASE-6309:
-----------------------------------------
Summary: [MTTR] Do NN operations outside of the ZK EventThread in
SplitLogManager
Key: HBASE-6309
URL: https://issues.apache.org/jira/browse/HBASE-6309
Project: HBase
Issue Type: Improvement
Affects Versions: 0.94.0, 0.92.1, 0.96.0
Reporter: Jean-Daniel Cryans
Priority: Critical
Fix For: 0.96.0
We found this issue during the leap second cataclysm which prompted a
distributed splitting of all our logs.
I saw that none of the RS were splitting after some time while the master was
showing that it wasn't even 30% done. jstack'ing I saw this:
{noformat}
"main-EventThread" daemon prio=10 tid=0x00007f6ce46d8800 nid=0x5376 in
Object.wait() [0x00007f6ce2ecb000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:485)
at org.apache.hadoop.ipc.Client.call(Client.java:1093)
- locked <0x00000005fdd661a0> (a org.apache.hadoop.ipc.Client$Call)
at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:226)
at $Proxy9.rename(Unknown Source)
at sun.reflect.GeneratedMethodAccessor29.invoke(Unknown Source)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at
org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:82)
at
org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:59)
at $Proxy9.rename(Unknown Source)
at org.apache.hadoop.hdfs.DFSClient.rename(DFSClient.java:759)
at
org.apache.hadoop.hdfs.DistributedFileSystem.rename(DistributedFileSystem.java:253)
at
org.apache.hadoop.hbase.regionserver.wal.HLogSplitter.moveRecoveredEditsFromTemp(HLogSplitter.java:553)
at
org.apache.hadoop.hbase.regionserver.wal.HLogSplitter.moveRecoveredEditsFromTemp(HLogSplitter.java:519)
at
org.apache.hadoop.hbase.master.SplitLogManager$1.finish(SplitLogManager.java:138)
at
org.apache.hadoop.hbase.master.SplitLogManager.getDataSetWatchSuccess(SplitLogManager.java:431)
at
org.apache.hadoop.hbase.master.SplitLogManager.access$1200(SplitLogManager.java:95)
at
org.apache.hadoop.hbase.master.SplitLogManager$GetDataAsyncCallback.processResult(SplitLogManager.java:1011)
at
org.apache.zookeeper.ClientCnxn$EventThread.processEvent(ClientCnxn.java:571)
at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:497)
{noformat}
We are effectively bottlenecking on doing NN operations and whatever else is
happening in GetDataAsyncCallback. It was so bad that on our 100 offline
cluster it took a few hours for the master to process all the incoming ZK
events while the actual splitting took a fraction of that time.
I'm marking this as critical and against 0.96 but depending on how involved the
fix is we might want to backport.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
