[
https://issues.apache.org/jira/browse/HBASE-22665?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16882290#comment-16882290
]
Wellington Chevreuil commented on HBASE-22665:
----------------------------------------------
Good summary, [~Apache9]! Agree with your assumptions here, but what if log
roll reaches _waitForSafepoint_ when _writerBroken_ is false, but no syncs ever
happen anymore? Maybe something like:
1) _syncFailed_ -> writerBroken is set to true -> no waiting for rolling yet ->
log roll is triggered by _syncFailed_
[here|https://github.com/apache/hbase/blob/branch-2.1/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.java#L320];
2) log roll triggered by syncFailed will get _waitForSafepoint,_ but since
_writerBroken_ is true, it doesn't wait;
3) log roll eventually reaches [this
point|https://github.com/apache/hbase/blob/branch-2.1/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.java#L673]
where _writerBroken_ state gets set back to false;
4) A periodic log roll is triggered, now this one will reach _waitForSafepoint_
with _writerBroken_ set to false, entering the waiting condition and with no
additional syncs, never leaving it;
Unfortunately, this code path does not add much logging messages that would
give more solid evidences on this.
> RegionServer abort failed when AbstractFSWAL.shutdown hang
> ----------------------------------------------------------
>
> Key: HBASE-22665
> URL: https://issues.apache.org/jira/browse/HBASE-22665
> Project: HBase
> Issue Type: Bug
> Environment: HBase 2.1.2
> Hadoop 3.1.x
> centos 7.4
> Reporter: Yechao Chen
> Priority: Major
> Attachments: image-2019-07-08-16-07-37-664.png,
> image-2019-07-08-16-08-26-777.png, image-2019-07-08-16-14-43-455.png,
> jstack_20190625, jstack_20190704_1, jstack_20190704_2, rs.log.part1,
> rs.log_part2.zip
>
>
> We use hbase 2.1.2,when the rs with heavy qps and rs abort with error like
> "Caused by: org.apache.hadoop.hbase.exceptions.TimeoutIOException: Failed to
> get sync result after 300000 ms for txid=36380334, WAL system stuck?"
>
> RegionServer aborted failed when AbstractFSWAL.shutdown hang
>
> jstack info always show the regionserver hang with "AbstractFSWAL.shutdown"
> "regionserver/hbase-slave-216-99:16020" #25 daemon prio=5 os_prio=0
> tid=0x00007f204282c600 nid=0x34aa waiting on condition [0x00007f0fe044d000]
> java.lang.Thread.State: WAITING (parking)
> at sun.misc.Unsafe.park(Native Method)
> - parking to wait for <0x00007f18a49b2bb8> (a
> java.util.concurrent.locks.ReentrantLock$FairSync)
> at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199)
> at
> java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:224)
> {color:#FF0000}at
> java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285){color}
> {color:#FF0000} at
> org.apache.hadoop.hbase.regionserver.wal.AbstractFSWAL.shutdown(AbstractFSWAL.java:815){color}
> at
> org.apache.hadoop.hbase.wal.AbstractFSWALProvider.shutdown(AbstractFSWALProvider.java:168)
> at
> org.apache.hadoop.hbase.wal.RegionGroupingProvider.shutdown(RegionGroupingProvider.java:221)
> at org.apache.hadoop.hbase.wal.WALFactory.shutdown(WALFactory.java:239)
> at
> org.apache.hadoop.hbase.regionserver.HRegionServer.shutdownWAL(HRegionServer.java:1445)
> {color:#FF0000}at
> org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:1117){color}
> {color:#FF0000} at java.lang.Thread.run(Thread.java:745){color}
>
>
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
