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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/36779/
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Review request for Ambari, Alejandro Fernandez, Nate Cole, and Sumit Mohanty.
Bugs: AMBARI-12526
https://issues.apache.org/jira/browse/AMBARI-12526
Repository: ambari
Description
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When deploying a new cluster on SQL Azure, there is a recurring deadlock on the
SQL Server.
Essentially, we have concurrent UPDATE statements in separate transactions
acting on different rows of hostcomponentstate. This seems to cause a deadlock
because both processes have an X lock and then try to acquire a U lock. The U
lock is what is making me think they are trying to acquire the table lock in
order to update the cluster index.
The solution was to:
- Ensure that some of the failing transactions were placed within the scope of
our internal Java locks
- flush writing to the problem table
Diffs
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ambari-server/src/main/java/org/apache/ambari/server/events/listeners/upgrade/HostVersionOutOfSyncListener.java
c016cbd
ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostComponentStateDAO.java
00ffd5a
ambari-server/src/main/java/org/apache/ambari/server/state/Host.java 7a53c21
ambari-server/src/main/java/org/apache/ambari/server/state/Service.java
1137cba
ambari-server/src/main/java/org/apache/ambari/server/state/ServiceComponent.java
60a16eb
ambari-server/src/main/java/org/apache/ambari/server/state/ServiceComponentHost.java
6917a15
ambari-server/src/main/java/org/apache/ambari/server/state/ServiceComponentImpl.java
aa147de
ambari-server/src/main/java/org/apache/ambari/server/state/ServiceImpl.java
6484c9f
ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java
2b3bf05
ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
90fdbec
ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java
a01f4d4
ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java
e59f4aa
ambari-server/src/main/java/org/apache/ambari/server/state/svccomphost/ServiceComponentHostImpl.java
b623479
ambari-server/src/test/java/org/apache/ambari/server/state/cluster/ServiceComponentHostConcurrentWriteDeadlockTest.java
PRE-CREATION
Diff: https://reviews.apache.org/r/36779/diff/
Testing
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Deployed on SQL Azure about 50 times and did not see the deadlock occur. It
would normally occur in the first 5 cluster deployments.
Thanks,
Jonathan Hurley
