[OAK-3493] Deadlock when closing a concurrently used FileStore 2.0

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.0.30, 1.2.14, 1.3.8, 1.4
• Component/s: segmentmk
• Labels: resilience
• Assignee: Michael Dürig
• Reporter: Michael Dürig
• Created: 07/Oct/15 13:27
• Updated: 24/Mar/16 13:35
• Resolved: 12/Oct/15 08:19

Description

A deadlock was detected while stopping the SegmentCompactionIT using the exposed MBean.

"main@1" prio=5 tid=0x1 nid=NA waiting for monitor entry
 waiting for pool-1-thread-10@2111 to release lock on <0xae8> (a org.apache.jackrabbit.oak.plugins.segment.SegmentWriter)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.dropCache(SegmentWriter.java:871)
  at org.apache.jackrabbit.oak.plugins.segment.file.FileStore.close(FileStore.java:1031)
  - locked <0xae7> (a org.apache.jackrabbit.oak.plugins.segment.file.FileStore)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentCompactionIT.tearDown(SegmentCompactionIT.java:282)

"pool-1-thread-10@2111" prio=5 tid=0x1d nid=NA waiting for monitor entry
  java.lang.Thread.State: BLOCKED
 blocks main@1
 waiting for main@1 to release lock on <0xae7> (a org.apache.jackrabbit.oak.plugins.segment.file.FileStore)
  at org.apache.jackrabbit.oak.plugins.segment.file.FileStore.writeSegment(FileStore.java:1155)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.flush(SegmentWriter.java:253)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.prepare(SegmentWriter.java:350)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.writeListBucket(SegmentWriter.java:468)
  - locked <0xae8> (a org.apache.jackrabbit.oak.plugins.segment.SegmentWriter)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.writeList(SegmentWriter.java:719)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.writeNode(SegmentWriter.java:1211)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter$2.childNodeChanged(SegmentWriter.java:1156)
  at org.apache.jackrabbit.oak.plugins.memory.ModifiedNodeState.compareAgainstBaseState(ModifiedNodeState.java:399)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.writeNode(SegmentWriter.java:1147)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentWriter.writeNode(SegmentWriter.java:1175)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentNodeBuilder.getNodeState(SegmentNodeBuilder.java:100)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentNodeStore$Commit.prepare(SegmentNodeStore.java:451)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentNodeStore$Commit.optimisticMerge(SegmentNodeStore.java:474)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentNodeStore$Commit.execute(SegmentNodeStore.java:530)
  at org.apache.jackrabbit.oak.plugins.segment.SegmentNodeStore.merge(SegmentNodeStore.java:208)

Issue Links

• relates to: OAK-3235 Deadlock when closing a concurrently used FileStore