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Posted to commits@cassandra.apache.org by "Sylvain Lebresne (JIRA)" <ji...@apache.org> on 2015/12/04 12:15:11 UTC

[jira] [Updated] (CASSANDRA-10815) WrappingCompactionStrategy can block others when there are lots of sstables

     [ https://issues.apache.org/jira/browse/CASSANDRA-10815?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Sylvain Lebresne updated CASSANDRA-10815:
-----------------------------------------
    Assignee: Marcus Eriksson

> WrappingCompactionStrategy can block others when there are lots of sstables
> ---------------------------------------------------------------------------
>
>                 Key: CASSANDRA-10815
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-10815
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Compaction
>            Reporter: Severin Leonhardt
>            Assignee: Marcus Eriksson
>             Fix For: 2.1.x, 2.2.x, 3.x
>
>
> We observe {{nodetool compactionstats}} hanging when there are a lot of SSTables in one table. We have about 30.000 SSTables most likely created by an incremental repair (why it's that many is still a mystery to us).
> Looking at the stacktraces of some selected threads it becomes apparent that a single CompactionExecutor blocks several other threads:
> {noformat}
> "CompactionExecutor:4065" - Thread t@282454
>    java.lang.Thread.State: RUNNABLE
> 	at java.util.TimSort.binarySort(TimSort.java:292)
> 	at java.util.TimSort.sort(TimSort.java:235)
> 	at java.util.Arrays.sort(Arrays.java:1512)
> 	at java.util.ArrayList.sort(ArrayList.java:1454)
> 	at java.util.Collections.sort(Collections.java:175)
> 	at org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy.trimToThresholdWithHotness(SizeTieredCompactionStrategy.java:139)
> 	at org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy.mostInterestingBucket(SizeTieredCompactionStrategy.java:119)
> 	at org.apache.cassandra.db.compaction.LeveledManifest.getSSTablesForSTCS(LeveledManifest.java:360)
> 	at org.apache.cassandra.db.compaction.LeveledManifest.getCompactionCandidates(LeveledManifest.java:318)
> 	- locked <25446e7b> (a org.apache.cassandra.db.compaction.LeveledManifest)
> 	at org.apache.cassandra.db.compaction.LeveledCompactionStrategy.getMaximalTask(LeveledCompactionStrategy.java:101)
> 	at org.apache.cassandra.db.compaction.LeveledCompactionStrategy.getNextBackgroundTask(LeveledCompactionStrategy.java:90)
> 	- locked <33506169> (a org.apache.cassandra.db.compaction.LeveledCompactionStrategy)
> 	at org.apache.cassandra.db.compaction.WrappingCompactionStrategy.getNextBackgroundTask(WrappingCompactionStrategy.java:77)
> 	- locked <31924612> (a org.apache.cassandra.db.compaction.WrappingCompactionStrategy)
> 	at org.apache.cassandra.db.compaction.CompactionManager$BackgroundCompactionCandidate.run(CompactionManager.java:230)
> 	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> 	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
> 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> 	at java.lang.Thread.run(Thread.java:745)
> {noformat}
> Because this thread has locked <31924612> (a org.apache.cassandra.db.compaction.WrappingCompactionStrategy) the following threads are blocked:
> {noformat}
> "CompactionExecutor:4064" - Thread t@282337
>    java.lang.Thread.State: BLOCKED
> 	at org.apache.cassandra.db.compaction.WrappingCompactionStrategy.getNextBackgroundTask(WrappingCompactionStrategy.java:72)
> 	- waiting to lock <31924612> (a org.apache.cassandra.db.compaction.WrappingCompactionStrategy) owned by "CompactionExecutor:4065" t@282454
> 	at org.apache.cassandra.db.compaction.CompactionManager$BackgroundCompactionCandidate.run(CompactionManager.java:230)
> 	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> 	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
> 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> 	at java.lang.Thread.run(Thread.java:745)
> {noformat}
> {noformat}
> "MemtableFlushWriter:2431" - Thread t@283411
>    java.lang.Thread.State: BLOCKED
> 	at org.apache.cassandra.db.compaction.WrappingCompactionStrategy.handleNotification(WrappingCompactionStrategy.java:250)
> 	- waiting to lock <31924612> (a org.apache.cassandra.db.compaction.WrappingCompactionStrategy) owned by "CompactionExecutor:4065" t@282454
> 	at org.apache.cassandra.db.DataTracker.notifyAdded(DataTracker.java:518)
> 	at org.apache.cassandra.db.DataTracker.replaceFlushed(DataTracker.java:178)
> 	at org.apache.cassandra.db.compaction.AbstractCompactionStrategy.replaceFlushed(AbstractCompactionStrategy.java:234)
> 	at org.apache.cassandra.db.ColumnFamilyStore.replaceFlushed(ColumnFamilyStore.java:1541)
> 	at org.apache.cassandra.db.Memtable$FlushRunnable.runMayThrow(Memtable.java:336)
> 	at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28)
> 	at com.google.common.util.concurrent.MoreExecutors$SameThreadExecutorService.execute(MoreExecutors.java:297)
> 	at org.apache.cassandra.db.ColumnFamilyStore$Flush.run(ColumnFamilyStore.java:1154)
> 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> 	at java.lang.Thread.run(Thread.java:745)
> {noformat}
> {noformat}
> "RMI TCP Connection(128577)-192.168.0.1" - Thread t@282977
>    java.lang.Thread.State: BLOCKED
> 	at org.apache.cassandra.db.compaction.WrappingCompactionStrategy.getEstimatedRemainingTasks(WrappingCompactionStrategy.java:147)
> 	- waiting to lock <31924612> (a org.apache.cassandra.db.compaction.WrappingCompactionStrategy) owned by "CompactionExecutor:4065" t@282454
> 	at org.apache.cassandra.metrics.CompactionMetrics$1.value(CompactionMetrics.java:65)
> 	at org.apache.cassandra.metrics.CompactionMetrics$1.value(CompactionMetrics.java:57)
> 	at com.yammer.metrics.reporting.JmxReporter$Gauge.getValue(JmxReporter.java:63)
> 	at sun.reflect.GeneratedMethodAccessor31.invoke(Unknown Source)
> 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> 	at java.lang.reflect.Method.invoke(Method.java:497)
> 	at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
> 	at sun.reflect.GeneratedMethodAccessor19.invoke(Unknown Source)
> 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> 	at java.lang.reflect.Method.invoke(Method.java:497)
> 	at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
> 	at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:112)
> 	at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:46)
> 	at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)
> 	at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)
> 	at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)
> 	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)
> 	at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)
> 	at com.sun.jmx.remote.security.MBeanServerAccessController.getAttribute(MBeanServerAccessController.java:320)
> 	at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1443)
> 	at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76)
> 	at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1307)
> 	at java.security.AccessController.doPrivileged(Native Method)
> 	at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1406)
> 	at javax.management.remote.rmi.RMIConnectionImpl.getAttribute(RMIConnectionImpl.java:637)
> 	at sun.reflect.GeneratedMethodAccessor21.invoke(Unknown Source)
> 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> 	at java.lang.reflect.Method.invoke(Method.java:497)
> 	at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:323)
> 	at sun.rmi.transport.Transport$1.run(Transport.java:200)
> 	at sun.rmi.transport.Transport$1.run(Transport.java:197)
> 	at java.security.AccessController.doPrivileged(Native Method)
> 	at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
> 	at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)
> 	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)
> 	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$241(TCPTransport.java:683)
> 	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler$$Lambda$1/183345253.run(Unknown Source)
> 	at java.security.AccessController.doPrivileged(Native Method)
> 	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)
> 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> 	at java.lang.Thread.run(Thread.java:745)
> {noformat}
> The lock protects from concurrent access through the two synchronized methods WrappingCompactionStrategy.getEstimatedRemainingTasks and WrappingCompactionStrategy.getNextBackgroundTask.
> The lock is not just hold for a short time but for several minutes. We think that this combined with suboptimal values for {{memtable_flush_writers}} and {{concurrent_compactors}} caused our nodes to exhaust their heap and die after running incremental repair.
> There also seems to be no other way to reduce the number of SSTables as a user except than waiting for the compactions to eventually finish which looks like it can take days.



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