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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/33158/
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(Updated April 14, 2015, 11:01 a.m.)
Review request for Ambari, Myroslav Papirkovskyy, Nate Cole, Sid Wagle, and Tom
Beerbower.
Bugs: AMBARI-10456
https://issues.apache.org/jira/browse/AMBARI-10456
Repository: ambari
Description
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When mapping hosts concurrently with reading information from a cluster, there
was a deadlock between the building the cluster health report and mapping the
new hosts.
A few changes to note here:
- ClustersImpl uses concurrent maps; there's really no need to keep the
internal lock. I removed it in several places where the cluster is guaranteed
to be available (such as when using the ID to retrieve the cluster). The
concurrent maps guard against concurrent modifications.
- The Ambari Event Publish was actually synchronous. This not only caused
bottlenecks, but also contributed to a secondary deadlock detected while fixing
the original issue. It was changed into a single-threaded asynchronous bus.
Consumers of this bus should never rely on it to perform its actions in order
to perform their own logic, so changing the behavior seemed correct
Diffs (updated)
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ambari-server/src/main/java/org/apache/ambari/server/events/publishers/AmbariEventPublisher.java
96e66a62
ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
9cf1f5a
ambari-server/src/main/java/org/apache/ambari/server/state/services/AmbariServerAlertService.java
89f9656
ambari-server/src/test/java/org/apache/ambari/server/agent/TestHeartbeatHandler.java
fe4ba60
ambari-server/src/test/java/org/apache/ambari/server/events/EventsTest.java
09c335a
ambari-server/src/test/java/org/apache/ambari/server/orm/dao/AlertDispatchDAOTest.java
8768ffc
ambari-server/src/test/java/org/apache/ambari/server/orm/dao/AlertsDAOTest.java
9c8ea7d
ambari-server/src/test/java/org/apache/ambari/server/state/alerts/AlertEventPublisherTest.java
19b5d46
ambari-server/src/test/java/org/apache/ambari/server/state/alerts/AlertStateChangedEventTest.java
b64afed
ambari-server/src/test/java/org/apache/ambari/server/state/alerts/InitialAlertEventTest.java
4e55c49
ambari-server/src/test/java/org/apache/ambari/server/state/cluster/AlertDataManagerTest.java
acf7911
ambari-server/src/test/java/org/apache/ambari/server/state/cluster/ClusterDeadlockTest.java
766105d
ambari-server/src/test/java/org/apache/ambari/server/state/cluster/ClustersDeadlockTest.java
839b25f
ambari-server/src/test/java/org/apache/ambari/server/utils/EventBusSynchronizer.java
PRE-CREATION
Diff: https://reviews.apache.org/r/33158/diff/
Testing
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New tests written to cover the deadlocks; existing tests updated for the async
event bus.
Thanks,
Jonathan Hurley
