[ https://issues.apache.org/jira/browse/CASSANDRA-13432?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Corentin Chary updated CASSANDRA-13432: --------------------------------------- Description: This might affect 3.x too, I'm not sure. {code} $ nodetool tpstats Pool Name Active Pending Completed Blocked All time blocked MutationStage 0 0 32135875 0 0 ReadStage 114 0 29492940 0 0 RequestResponseStage 0 0 86090931 0 0 ReadRepairStage 0 0 166645 0 0 CounterMutationStage 0 0 0 0 0 MiscStage 0 0 0 0 0 HintedHandoff 0 0 47 0 0 GossipStage 0 0 188769 0 0 CacheCleanupExecutor 0 0 0 0 0 InternalResponseStage 0 0 0 0 0 CommitLogArchiver 0 0 0 0 0 CompactionExecutor 0 0 86835 0 0 ValidationExecutor 0 0 0 0 0 MigrationStage 0 0 0 0 0 AntiEntropyStage 0 0 0 0 0 PendingRangeCalculator 0 0 92 0 0 Sampler 0 0 0 0 0 MemtableFlushWriter 0 0 563 0 0 MemtablePostFlush 0 0 1500 0 0 MemtableReclaimMemory 1 29 534 0 0 Native-Transport-Requests 41 0 54819182 0 1896 {code} {code} "MemtableReclaimMemory:195" - Thread t@6268 java.lang.Thread.State: WAITING at sun.misc.Unsafe.park(Native Method) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:304) at org.apache.cassandra.utils.concurrent.WaitQueue$AbstractSignal.awaitUninterruptibly(WaitQueue.java:283) at org.apache.cassandra.utils.concurrent.OpOrder$Barrier.await(OpOrder.java:417) at org.apache.cassandra.db.ColumnFamilyStore$Flush$1.runMayThrow(ColumnFamilyStore.java:1151) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - locked <6e7b1160> (a java.util.concurrent.ThreadPoolExecutor$Worker) "SharedPool-Worker-195" - Thread t@989 java.lang.Thread.State: RUNNABLE at org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) at org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) at org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) at org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) at org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) at org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) at org.apache.cassandra.utils.MergeIterator$ManyToOne.advance(MergeIterator.java:125) at org.apache.cassandra.utils.MergeIterator$ManyToOne.computeNext(MergeIterator.java:99) at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143) at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138) at org.apache.cassandra.db.filter.SliceQueryFilter.collectReducedColumns(SliceQueryFilter.java:263) at org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:108) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) at org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) at org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) at org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) at org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None "SharedPool-Worker-206" - Thread t@1014 java.lang.Thread.State: RUNNABLE at org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) at org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) at org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) at org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) at org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) at org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) at org.apache.cassandra.utils.MergeIterator$ManyToOne.<init>(MergeIterator.java:89) at org.apache.cassandra.utils.MergeIterator.get(MergeIterator.java:48) at org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:105) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) at org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) at org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) at org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) at org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None {code} As you can see MemtableReclaimMemory is waiting on the read barrier to be released, but there are two queries currently being executed which are locking this. Since most of the time is spent pretty low in the stack, these read operations will never timeout (they are reading rows with tons of tombstones). We also can easily detect or purge the offending line because there is no easy way to find out which partition is currently being read. The TombstoneFailureThreshold should also protect us, but it is probably being checked too high in the call stack. Looks like RangeTombstoneList or DeletionInfo should also check for DatabaseDescriptor.getTombstoneFailureThreshold() was: This might affect 3.x too, I'm not sure. {code} $ nodetool tpstats Pool Name Active Pending Completed Blocked All time blocked MutationStage 0 0 32135875 0 0 ReadStage 114 0 29492940 0 0 RequestResponseStage 0 0 86090931 0 0 ReadRepairStage 0 0 166645 0 0 CounterMutationStage 0 0 0 0 0 MiscStage 0 0 0 0 0 HintedHandoff 0 0 47 0 0 GossipStage 0 0 188769 0 0 CacheCleanupExecutor 0 0 0 0 0 InternalResponseStage 0 0 0 0 0 CommitLogArchiver 0 0 0 0 0 CompactionExecutor 0 0 86835 0 0 ValidationExecutor 0 0 0 0 0 MigrationStage 0 0 0 0 0 AntiEntropyStage 0 0 0 0 0 PendingRangeCalculator 0 0 92 0 0 Sampler 0 0 0 0 0 MemtableFlushWriter 0 0 563 0 0 MemtablePostFlush 0 0 1500 0 0 MemtableReclaimMemory 1 29 534 0 0 Native-Transport-Requests 41 0 54819182 0 1896 {code} {code} "MemtableReclaimMemory:195" - Thread t@6268 java.lang.Thread.State: WAITING at sun.misc.Unsafe.park(Native Method) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:304) at org.apache.cassandra.utils.concurrent.WaitQueue$AbstractSignal.awaitUninterruptibly(WaitQueue.java:283) at org.apache.cassandra.utils.concurrent.OpOrder$Barrier.await(OpOrder.java:417) at org.apache.cassandra.db.ColumnFamilyStore$Flush$1.runMayThrow(ColumnFamilyStore.java:1151) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - locked <6e7b1160> (a java.util.concurrent.ThreadPoolExecutor$Worker) "SharedPool-Worker-195" - Thread t@989 java.lang.Thread.State: RUNNABLE at org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) at org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) at org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) at org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) at org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) at org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) at org.apache.cassandra.utils.MergeIterator$ManyToOne.advance(MergeIterator.java:125) at org.apache.cassandra.utils.MergeIterator$ManyToOne.computeNext(MergeIterator.java:99) at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143) at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138) at org.apache.cassandra.db.filter.SliceQueryFilter.collectReducedColumns(SliceQueryFilter.java:263) at org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:108) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) at org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) at org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) at org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) at org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None "SharedPool-Worker-206" - Thread t@1014 java.lang.Thread.State: RUNNABLE at org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) at org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) at org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) at org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) at org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) at org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) at org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) at org.apache.cassandra.utils.MergeIterator$ManyToOne.<init>(MergeIterator.java:89) at org.apache.cassandra.utils.MergeIterator.get(MergeIterator.java:48) at org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:105) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) at org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) at org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) at org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) at org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) at org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None {code} As you can see MemtableReclaimMemory is waiting on the read barrier to be released, but there are two queries currently being executed which are locking this. Since most of the time is spent pretty low in the stack, these read operations will never timeout (they are reading rows with tons of tombstones). We also can easily detect or purge the offending line because there is no easy way to find out which partition is currently being read. The TombstoneFailureThreshold should also protect us, but it is probably being checked too high in the call stack. > MemtableReclaimMemory can get stuck because of lack of timeout in > getTopLevelColumns() > -------------------------------------------------------------------------------------- > > Key: CASSANDRA-13432 > URL: https://issues.apache.org/jira/browse/CASSANDRA-13432 > Project: Cassandra > Issue Type: Bug > Reporter: Corentin Chary > Fix For: 2.1.x > > > This might affect 3.x too, I'm not sure. > {code} > $ nodetool tpstats > Pool Name Active Pending Completed Blocked All > time blocked > MutationStage 0 0 32135875 0 > 0 > ReadStage 114 0 29492940 0 > 0 > RequestResponseStage 0 0 86090931 0 > 0 > ReadRepairStage 0 0 166645 0 > 0 > CounterMutationStage 0 0 0 0 > 0 > MiscStage 0 0 0 0 > 0 > HintedHandoff 0 0 47 0 > 0 > GossipStage 0 0 188769 0 > 0 > CacheCleanupExecutor 0 0 0 0 > 0 > InternalResponseStage 0 0 0 0 > 0 > CommitLogArchiver 0 0 0 0 > 0 > CompactionExecutor 0 0 86835 0 > 0 > ValidationExecutor 0 0 0 0 > 0 > MigrationStage 0 0 0 0 > 0 > AntiEntropyStage 0 0 0 0 > 0 > PendingRangeCalculator 0 0 92 0 > 0 > Sampler 0 0 0 0 > 0 > MemtableFlushWriter 0 0 563 0 > 0 > MemtablePostFlush 0 0 1500 0 > 0 > MemtableReclaimMemory 1 29 534 0 > 0 > Native-Transport-Requests 41 0 54819182 0 > 1896 > {code} > {code} > "MemtableReclaimMemory:195" - Thread t@6268 > java.lang.Thread.State: WAITING > at sun.misc.Unsafe.park(Native Method) > at java.util.concurrent.locks.LockSupport.park(LockSupport.java:304) > at > org.apache.cassandra.utils.concurrent.WaitQueue$AbstractSignal.awaitUninterruptibly(WaitQueue.java:283) > at > org.apache.cassandra.utils.concurrent.OpOrder$Barrier.await(OpOrder.java:417) > at > org.apache.cassandra.db.ColumnFamilyStore$Flush$1.runMayThrow(ColumnFamilyStore.java:1151) > at > org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28) > at > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) > at java.lang.Thread.run(Thread.java:745) > Locked ownable synchronizers: > - locked <6e7b1160> (a java.util.concurrent.ThreadPoolExecutor$Worker) > "SharedPool-Worker-195" - Thread t@989 > java.lang.Thread.State: RUNNABLE > at > org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) > at > org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) > at > org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) > at > org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) > at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) > at > org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) > at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) > at > org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) > at > org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) > at > org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) > at > org.apache.cassandra.utils.MergeIterator$ManyToOne.advance(MergeIterator.java:125) > at > org.apache.cassandra.utils.MergeIterator$ManyToOne.computeNext(MergeIterator.java:99) > at > com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143) > at > com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138) > at > org.apache.cassandra.db.filter.SliceQueryFilter.collectReducedColumns(SliceQueryFilter.java:263) > at > org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:108) > at > org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) > at > org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) > at > org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) > at > org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) > at > org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) > at > org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) > at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) > at > org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) > at > org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) > at > org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) > at > java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) > at > org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) > at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) > at java.lang.Thread.run(Thread.java:745) > Locked ownable synchronizers: > - None > "SharedPool-Worker-206" - Thread t@1014 > java.lang.Thread.State: RUNNABLE > at > org.apache.cassandra.db.RangeTombstoneList.addInternal(RangeTombstoneList.java:690) > at > org.apache.cassandra.db.RangeTombstoneList.insertFrom(RangeTombstoneList.java:650) > at > org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:171) > at > org.apache.cassandra.db.RangeTombstoneList.add(RangeTombstoneList.java:143) > at org.apache.cassandra.db.DeletionInfo.add(DeletionInfo.java:240) > at > org.apache.cassandra.db.ArrayBackedSortedColumns.delete(ArrayBackedSortedColumns.java:483) > at org.apache.cassandra.db.ColumnFamily.addAtom(ColumnFamily.java:153) > at > org.apache.cassandra.db.filter.QueryFilter$2.getNext(QueryFilter.java:184) > at > org.apache.cassandra.db.filter.QueryFilter$2.hasNext(QueryFilter.java:156) > at > org.apache.cassandra.utils.MergeIterator$Candidate.advance(MergeIterator.java:146) > at > org.apache.cassandra.utils.MergeIterator$ManyToOne.<init>(MergeIterator.java:89) > at org.apache.cassandra.utils.MergeIterator.get(MergeIterator.java:48) > at > org.apache.cassandra.db.filter.QueryFilter.collateColumns(QueryFilter.java:105) > at > org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:82) > at > org.apache.cassandra.db.filter.QueryFilter.collateOnDiskAtom(QueryFilter.java:69) > at > org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:316) > at > org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:62) > at > org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2015) > at > org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1858) > at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:353) > at > org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85) > at > org.apache.cassandra.db.ReadVerbHandler.doVerb(ReadVerbHandler.java:47) > at > org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:64) > at > java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) > at > org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164) > at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105) > at java.lang.Thread.run(Thread.java:745) > Locked ownable synchronizers: > - None > {code} > As you can see MemtableReclaimMemory is waiting on the read barrier to be > released, but there are two queries currently being executed which are > locking this. > Since most of the time is spent pretty low in the stack, these read > operations will never timeout (they are reading rows with tons of tombstones). > We also can easily detect or purge the offending line because there is no > easy way to find out which partition is currently being read. > The TombstoneFailureThreshold should also protect us, but it is probably > being checked too high in the call stack. > Looks like RangeTombstoneList or DeletionInfo should also check for > DatabaseDescriptor.getTombstoneFailureThreshold() -- This message was sent by Atlassian JIRA (v6.3.15#6346)