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https://issues.apache.org/jira/browse/AMBARI-12570?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jonathan Hurley updated AMBARI-12570:
-------------------------------------
    Fix Version/s:     (was: 2.1.1)
                   2.2.0

> Cluster creates stuck at 9x% (deadlock sql exception)
> -----------------------------------------------------
>
>                 Key: AMBARI-12570
>                 URL: https://issues.apache.org/jira/browse/AMBARI-12570
>             Project: Ambari
>          Issue Type: Bug
>    Affects Versions: 2.1.0
>            Reporter: Jonathan Hurley
>            Assignee: Jonathan Hurley
>            Priority: Blocker
>             Fix For: 2.2.0
>
>         Attachments: AMBARI-12570.patch, AMBARI-12570.patch.1
>
>
> Similar to AMBARI-12526, Ambari installation via a blueprint on SQL Azure 
> gets stuck somewhere between 90% and 100% because of a SQL Database deadlock. 
> This is always between {{hostcomponentstate.current_state}} and 
> {{hostcomponentstate.version}}. 
> {code}
> Rollback reason: 
> Local Exception Stack: 
> Exception [EclipseLink-4002] (Eclipse Persistence Services - 
> 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.DatabaseException
> Internal Exception: com.microsoft.sqlserver.jdbc.SQLServerException: 
> Transaction (Process ID 62) was deadlocked on lock resources with another 
> process and has been chosen as the deadlock victim. Rerun the transaction.
> Error Code: 1205
> Call: UPDATE hostcomponentstate SET current_state = ? WHERE 
> ((((component_name = ?) AND (host_id = ?)) AND (cluster_id = ?)) AND 
> (service_name = ?))
>       bind => [5 parameters bound]
>       at 
> org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:331)
>       at 
> org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeDirectNoSelect(DatabaseAccessor.java:900)
>       at 
> org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeNoSelect(DatabaseAccessor.java:962)
>       at 
> org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:631)
>       at 
> org.eclipse.persistence.internal.databaseaccess.ParameterizedSQLBatchWritingMechanism.executeBatch(ParameterizedSQLBatchWritingMechanism.java:149)
>       at 
> org.eclipse.persistence.internal.databaseaccess.ParameterizedSQLBatchWritingMechanism.executeBatchedStatements(ParameterizedSQLBatchWritingMechanism.java:134)
>       at 
> org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.writesCompleted(DatabaseAccessor.java:1836)
>       at 
> org.eclipse.persistence.internal.sessions.AbstractSession.writesCompleted(AbstractSession.java:4244)
>       at 
> org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.writesCompleted(UnitOfWorkImpl.java:5594)
>       at 
> org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.writeChanges(RepeatableWriteUnitOfWork.java:453)
>       at 
> org.eclipse.persistence.internal.jpa.EntityManagerImpl.flush(EntityManagerImpl.java:863)
>       at 
> org.eclipse.persistence.internal.jpa.QueryImpl.performPreQueryFlush(QueryImpl.java:963)
>       at 
> org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:207)
>       at 
> org.eclipse.persistence.internal.jpa.QueryImpl.getSingleResult(QueryImpl.java:517)
>       at 
> org.eclipse.persistence.internal.jpa.EJBQueryImpl.getSingleResult(EJBQueryImpl.java:400)
>       at org.apache.ambari.server.orm.dao.DaoUtils.selectOne(DaoUtils.java:80)
>       at org.apache.ambari.server.orm.dao.StackDAO.find(StackDAO.java:93)
>       at 
> org.apache.ambari.server.orm.AmbariLocalSessionInterceptor.invoke(AmbariLocalSessionInterceptor.java:53)
>       at 
> org.apache.ambari.server.state.svccomphost.ServiceComponentHostImpl.setStackVersion(ServiceComponentHostImpl.java:1058)
>       at 
> org.apache.ambari.server.state.svccomphost.ServiceComponentHostImpl$ServiceComponentHostOpStartedTransition.transition(ServiceComponentHostImpl.java:628)
>       at 
> org.apache.ambari.server.state.svccomphost.ServiceComponentHostImpl$ServiceComponentHostOpStartedTransition.transition(ServiceComponentHostImpl.java:610)
>       at 
> org.apache.ambari.server.state.fsm.StateMachineFactory$SingleInternalArc.doTransition(StateMachineFactory.java:354)
>       at 
> org.apache.ambari.server.state.fsm.StateMachineFactory.doTransition(StateMachineFactory.java:294)
>       at 
> org.apache.ambari.server.state.fsm.StateMachineFactory.access$300(StateMachineFactory.java:39)
>       at 
> org.apache.ambari.server.state.fsm.StateMachineFactory$InternalStateMachine.doTransition(StateMachineFactory.java:440)
>       at 
> org.apache.ambari.server.state.svccomphost.ServiceComponentHostImpl.handleEvent(ServiceComponentHostImpl.java:901)
>       at 
> org.apache.ambari.server.state.cluster.ClusterImpl.processServiceComponentHostEvents(ClusterImpl.java:2508)
>       at 
> org.apache.ambari.server.orm.AmbariJpaLocalTxnInterceptor.invoke(AmbariJpaLocalTxnInterceptor.java:68)
>       at 
> org.apache.ambari.server.actionmanager.ActionScheduler.doWork(ActionScheduler.java:343)
>       at 
> org.apache.ambari.server.actionmanager.ActionScheduler.run(ActionScheduler.java:195)
>       at java.lang.Thread.run(Thread.java:745)
> {code}
> - We have dual X-locks on {{hostcomponentstate}} asking for U-locks when 
> updating the CLUSTERED INDEX.
> - Both dual X-locks, from different transactions and different processes, are 
> on the same row (technically impossible) - based on the XML execution plan, 
> we can see that the concurrent UPDATE statements are executing on different 
> rows due to their CLUSTERED INDEX predicate.
> - In Java, Ambari has locks which prevent concurrent U- or X-locks on the 
> same row
> - Only happens on SQL Server
> My best suspicion right now is that we have a key hash collision happening on 
> this table. That's why two processes appear to have the same lock even though 
> they are on different rows. 
> I was able to use a database dump that I took to compare hash values from 
> {{hostcomponentstate}}:
> {code:sql}
> SELECT  %%lockres%% as lock_hash, cluster_id, host_id, service_name, 
> component_name
>   FROM hostcomponentstate 
>   ORDER BY host_id, service_name, %%lockres%%
> {code}
> {code}
> lock_hash     cluster_id      host_id service_name    component_name
> (0d4a8b0869f5)        2       1       HDFS    SECONDARY_NAMENODE
> (0d4a8b0869f5)        2       1       HDFS    HDFS_CLIENT
> (99fb0081b824)        2       1       MAPREDUCE2      HISTORYSERVER
> (7086998db3dc)        2       1       YARN    APP_TIMELINE_SERVER
> (7086998db3dc)        2       1       YARN    RESOURCEMANAGER
> (3bef52323322)        2       1       ZOOKEEPER       ZOOKEEPER_SERVER
> ...
> {code}
> SQL Server is producing lock hashes that collide! It seems like the issue 
> here is that we are using a CLUSTERED INDEX on 4 columns, 3 of which are 
> always the same (cluster, host, service) in many cases. The only variable is 
> the component name. When the hash gets truncated to 6 bytes, we get 
> duplicates. 
> So, I think this totally aligns with my suspicions as to why this is only a 
> SQL Server problem since other database don't lock like this. It also makes 
> sense that this is the only table this happens on since we are not using a 
> surrogate PK here. I think we have a few options here:
> - Add more columns into the CLUSTERED INDEX in hopes we get a more unique 
> hash. The problem is that the other columns are also basically the same.
> - Change the CLUSTERED INDEX to an UNCLUSTERED INDEX (since this is our main 
> query criteria) and use a single, unique BIGINT PK as we do for many other 
> tables. I'm just not sure how SQL Server locks on a row when there is a 
> CLUSTERED INDEX which is not part of the predicate.
> - Remove the CLUSTERED INDEX entirely (performance would probably tank)
> - It's possible we can try to partition this table differently so that lock 
> space is more unique.
> - Change the existing CLUSTERED INDEX so that it disallows row and page level 
> locks, forcing all X-locks to be table-level locks. This would, in theory, 
> prevent the deadlock and would not require us to change any data. But it 
> would introduce a bottleneck on the table for anything more than a single 
> read.



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