i'm seeing a lot of these ... any idea?
2010-03-04 18:53:21,455 ERROR [MEMTABLE-POST-FLUSHER:1] [DebuggableThreadPoolExecutor.java:94] Error in executor futuretask java.util.concurrent.ExecutionException: java.lang.RuntimeException: java.lang.RuntimeException: java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at java.util.concurrent.FutureTask.get(FutureTask.java:83) at org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor.afterExecute(DebuggableThreadPoolExecutor.java:86) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:888) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.lang.RuntimeException: java.lang.RuntimeException: java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:34) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) ... 2 more Caused by: java.lang.RuntimeException: java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException at org.apache.cassandra.db.commitlog.CommitLog.discardCompletedSegments(CommitLog.java:357) at org.apache.cassandra.db.ColumnFamilyStore$2.runMayThrow(ColumnFamilyStore.java:392) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 6 more Caused by: java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at java.util.concurrent.FutureTask.get(FutureTask.java:83) at org.apache.cassandra.db.commitlog.CommitLog.discardCompletedSegments(CommitLog.java:349) ... 8 more Caused by: java.util.ConcurrentModificationException at java.util.ArrayDeque$DeqIterator.next(ArrayDeque.java:605) at org.apache.cassandra.db.commitlog.CommitLog.discardCompletedSegmentsInternal(CommitLog.java:385) at org.apache.cassandra.db.commitlog.CommitLog.access$300(CommitLog.java:71) at org.apache.cassandra.db.commitlog.CommitLog$6.call(CommitLog.java:343) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at org.apache.cassandra.db.commitlog.CommitLogExecutorService.process(CommitLogExecutorService.java:113) at org.apache.cassandra.db.commitlog.CommitLogExecutorService.access$200(CommitLogExecutorService.java:35) at org.apache.cassandra.db.commitlog.CommitLogExecutorService$1.runMayThrow(CommitLogExecutorService.java:67) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 1 more