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https://issues.apache.org/jira/browse/CASSANDRA-7275?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14246852#comment-14246852
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Benedict commented on CASSANDRA-7275:
-------------------------------------
I'm not sure this really improves the current state of affairs very much, and
introduces a bug as well.
If we fail to flush and simply carry on without clearing the CL, then the host
will retain the memtable it wanted to flush forever, leaving it in a
potentially severely degraded state (increasing risk of exceeding heap limit,
or possible failing to ever accept writes in 2.1 due to insufficient memory).
If the same table has another flush backed up (or another is later scheduled)
then we will also end up expiring the commit log records anyway, despite not
having flushed successfully.
Either we need to reattempt the flush, prevent any further flushes on that
column family from ever succeeding, or - more simply - kill the C* process.
> Errors in FlushRunnable may leave threads hung
> ----------------------------------------------
>
> Key: CASSANDRA-7275
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7275
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Tyler Hobbs
> Assignee: Pavel Yaskevich
> Priority: Minor
> Fix For: 2.0.12
>
> Attachments: 0001-Move-latch.countDown-into-finally-block.patch,
> 7252-2.0-v2.txt, CASSANDRA-7275-flush-info.patch
>
>
> In Memtable.FlushRunnable, the CountDownLatch will never be counted down if
> there are errors, which results in hanging any threads that are waiting for
> the flush to complete. For example, an error like this causes the problem:
> {noformat}
> ERROR [FlushWriter:474] 2014-05-20 12:10:31,137 CassandraDaemon.java (line
> 198) Exception in thread Thread[FlushWriter:474,5,main]
> java.lang.IllegalArgumentException
> at java.nio.Buffer.position(Unknown Source)
> at
> org.apache.cassandra.db.marshal.AbstractCompositeType.getBytes(AbstractCompositeType.java:64)
> at
> org.apache.cassandra.db.marshal.AbstractCompositeType.getWithShortLength(AbstractCompositeType.java:72)
> at
> org.apache.cassandra.db.marshal.AbstractCompositeType.split(AbstractCompositeType.java:138)
> at
> org.apache.cassandra.io.sstable.ColumnNameHelper.minComponents(ColumnNameHelper.java:103)
> at
> org.apache.cassandra.db.ColumnFamily.getColumnStats(ColumnFamily.java:439)
> at
> org.apache.cassandra.io.sstable.SSTableWriter.append(SSTableWriter.java:194)
> at
> org.apache.cassandra.db.Memtable$FlushRunnable.writeSortedContents(Memtable.java:397)
> at
> org.apache.cassandra.db.Memtable$FlushRunnable.runWith(Memtable.java:350)
> at
> org.apache.cassandra.io.util.DiskAwareRunnable.runMayThrow(DiskAwareRunnable.java:48)
> at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28)
> at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
> at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
> at java.lang.Thread.run(Unknown Source)
> {noformat}
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