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https://issues.apache.org/jira/browse/CASSANDRA-7275?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14247461#comment-14247461
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Benedict commented on CASSANDRA-7275:
-------------------------------------
What happens if the process stays up longer than tombstone grace period? Or we
introduce CASSANDRA-6434? This approach seems like a minefield to me, ignoring
the operational risks of running a very degraded server without the operators
realising it.
Generally we take the approach of dying if a non-recoverable error occurs, and
while I agree the risk of killing a whole cluster through a bug is suboptimal,
we already run that risk in a number of places in the codebase (current
behaviour here included, just with less alacrity). In my opinion this is
preferable to potentially re-introducing dead data, or having the complexity of
safely keeping the process alive as a zombie, and ensuring that zombie doesn't
degrade cluster performance by hobbling instead of dying.
Other than dying, periodically trying to reflush and only keeling over when we
run out of room or have failed for a long period (possibly random? to avoid the
tiny risk of bunching) seems like a good idea.
> 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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