[
https://issues.apache.org/jira/browse/HBASE-9321?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13749124#comment-13749124
]
Jimmy Xiang commented on HBASE-9321:
------------------------------------
To avoid creating too many connections, if the current user is different from
the user who set up the connection, we pass the current user to the server in
one header so the server knows it's calling on behalf of a different user.
If security is enabled, we can cache the user if user proxying is not supported
(configuration). Let me do a patch.
> Contention getting the current user in RpcClient$Connection.writeRequest
> ------------------------------------------------------------------------
>
> Key: HBASE-9321
> URL: https://issues.apache.org/jira/browse/HBASE-9321
> Project: HBase
> Issue Type: Bug
> Affects Versions: 0.95.2
> Reporter: Jean-Daniel Cryans
> Fix For: 0.98.0, 0.96.0
>
>
> I've been running tests on clusters with "lots" of regions, about 400, and
> I'm seeing weird contention in the client.
> This one I see a lot, hundreds and sometimes thousands of threads are blocked
> like this:
> {noformat}
> "htable-pool4-t74" daemon prio=10 tid=0x00007f2254114000 nid=0x2a99 waiting
> for monitor entry [0x00007f21f9e94000]
> java.lang.Thread.State: BLOCKED (on object monitor)
> at
> org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:466)
> - waiting to lock <0x00000000fb5ad000> (a java.lang.Class for
> org.apache.hadoop.security.UserGroupInformation)
> at
> org.apache.hadoop.hbase.ipc.RpcClient$Connection.writeRequest(RpcClient.java:1013)
> at org.apache.hadoop.hbase.ipc.RpcClient.call(RpcClient.java:1407)
> at
> org.apache.hadoop.hbase.ipc.RpcClient.callBlockingMethod(RpcClient.java:1634)
> at
> org.apache.hadoop.hbase.ipc.RpcClient$BlockingRpcChannelImplementation.callBlockingMethod(RpcClient.java:1691)
> at
> org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$BlockingStub.multi(ClientProtos.java:27339)
> at
> org.apache.hadoop.hbase.client.MultiServerCallable.call(MultiServerCallable.java:105)
> at
> org.apache.hadoop.hbase.client.MultiServerCallable.call(MultiServerCallable.java:43)
> at
> org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:183)
> {noformat}
> While the holder is doing this:
> {noformat}
> "htable-pool17-t55" daemon prio=10 tid=0x00007f2244408000 nid=0x2a98 runnable
> [0x00007f21f9f95000]
> java.lang.Thread.State: RUNNABLE
> at java.security.AccessController.getStackAccessControlContext(Native
> Method)
> at java.security.AccessController.getContext(AccessController.java:487)
> at
> org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:466)
> - locked <0x00000000fb5ad000> (a java.lang.Class for
> org.apache.hadoop.security.UserGroupInformation)
> at
> org.apache.hadoop.hbase.ipc.RpcClient$Connection.writeRequest(RpcClient.java:1013)
> at org.apache.hadoop.hbase.ipc.RpcClient.call(RpcClient.java:1407)
> at
> org.apache.hadoop.hbase.ipc.RpcClient.callBlockingMethod(RpcClient.java:1634)
> at
> org.apache.hadoop.hbase.ipc.RpcClient$BlockingRpcChannelImplementation.callBlockingMethod(RpcClient.java:1691)
> at
> org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$BlockingStub.multi(ClientProtos.java:27339)
> at
> org.apache.hadoop.hbase.client.MultiServerCallable.call(MultiServerCallable.java:105)
> at
> org.apache.hadoop.hbase.client.MultiServerCallable.call(MultiServerCallable.java:43)
> at
> org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:183)
> {noformat}
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
