[CASSANDRA-12764] Compaction performance issues with many sstables, during transaction commit phase

• Type: Bug
• Status: Open
• Priority: Normal
• Resolution: Unresolved
• Component/s: Local/Compaction
• Labels: lcs performance
• Severity: Normal
• Assignee: Unassigned Assign to me
• Reporter: Tom van der Woerdt
• Created: 09/Oct/16 23:01
• Updated: 02/Aug/19 19:38

Description

An issue with a script flooded my cluster with sstables. There is now a table with 100k sstables, all on the order of KBytes, and it's taking a long time (ETA 20 days) to compact, even though the table is only ~30GB.

Stack trace :

"CompactionExecutor:308" #7541 daemon prio=1 os_prio=4 tid=0x00007fa22af35400 nid=0x41eb runnable [0x00007fdbea48d000]
   java.lang.Thread.State: RUNNABLE
	at java.util.TimSort.countRunAndMakeAscending(TimSort.java:360)
	at java.util.TimSort.sort(TimSort.java:220)
	at java.util.Arrays.sort(Arrays.java:1438)
	at com.google.common.collect.Ordering.sortedCopy(Ordering.java:817)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:209)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:211)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:210)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:210)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:210)
	at org.apache.cassandra.utils.IntervalTree$IntervalNode.<init>(IntervalTree.java:210)
	at org.apache.cassandra.utils.IntervalTree.<init>(IntervalTree.java:50)
	at org.apache.cassandra.db.lifecycle.SSTableIntervalTree.<init>(SSTableIntervalTree.java:40)
	at org.apache.cassandra.db.lifecycle.SSTableIntervalTree.build(SSTableIntervalTree.java:50)
	at org.apache.cassandra.db.lifecycle.View$4.apply(View.java:288)
	at org.apache.cassandra.db.lifecycle.View$4.apply(View.java:283)
	at com.google.common.base.Functions$FunctionComposition.apply(Functions.java:216)
	at org.apache.cassandra.db.lifecycle.Tracker.apply(Tracker.java:128)
	at org.apache.cassandra.db.lifecycle.Tracker.apply(Tracker.java:101)
	at org.apache.cassandra.db.lifecycle.LifecycleTransaction.checkpoint(LifecycleTransaction.java:307)
	at org.apache.cassandra.db.lifecycle.LifecycleTransaction.checkpoint(LifecycleTransaction.java:288)
	at org.apache.cassandra.io.sstable.SSTableRewriter.doPrepare(SSTableRewriter.java:368)
	at org.apache.cassandra.utils.concurrent.Transactional$AbstractTransactional.prepareToCommit(Transactional.java:173)
	at org.apache.cassandra.db.compaction.writers.CompactionAwareWriter.doPrepare(CompactionAwareWriter.java:84)
	at org.apache.cassandra.utils.concurrent.Transactional$AbstractTransactional.prepareToCommit(Transactional.java:173)
	at org.apache.cassandra.utils.concurrent.Transactional$AbstractTransactional.finish(Transactional.java:184)
	at org.apache.cassandra.db.compaction.writers.CompactionAwareWriter.finish(CompactionAwareWriter.java:94)
	at org.apache.cassandra.db.compaction.CompactionTask.runMayThrow(CompactionTask.java:194)
	at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28)
	at org.apache.cassandra.db.compaction.CompactionTask.executeInternal(CompactionTask.java:78)
	at org.apache.cassandra.db.compaction.AbstractCompactionTask.execute(AbstractCompactionTask.java:61)
	at org.apache.cassandra.db.compaction.CompactionManager$BackgroundCompactionCandidate.run(CompactionManager.java:263)
	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)

IntervalTree shows in a lot of stack traces I've taken on several nodes.