HBASE-21228 Memory leak since AbstractFSWAL caches Thread object and never clean later
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/9321f7d8 Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/9321f7d8 Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/9321f7d8 Branch: refs/heads/branch-1.3 Commit: 9321f7d86cb1eee4508d96f261189b90b85e714c Parents: 10e4868 Author: Allan Yang <allan...@apache.org> Authored: Thu Sep 27 16:44:46 2018 +0800 Committer: Andrew Purtell <apurt...@apache.org> Committed: Thu Sep 27 17:51:43 2018 -0700 ---------------------------------------------------------------------- .../hadoop/hbase/regionserver/wal/FSHLog.java | 26 +++++++++----------- 1 file changed, 12 insertions(+), 14 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/hbase/blob/9321f7d8/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java ---------------------------------------------------------------------- diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java index f508bd7..eb734bb 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java @@ -190,12 +190,11 @@ public class FSHLog implements WAL { private final RingBufferEventHandler ringBufferEventHandler; /** - * Map of {@link SyncFuture}s keyed by Handler objects. Used so we reuse SyncFutures. - * TODO: Reus FSWALEntry's rather than create them anew each time as we do SyncFutures here. - * TODO: Add a FSWalEntry and SyncFuture as thread locals on handlers rather than have them - * get them from this Map? + * Map of {@link SyncFuture}s owned by Thread objects. Used so we reuse SyncFutures. + * Thread local is used so JVM can GC the terminated thread for us. See HBASE-21228 + * <p> */ - private final Map<Thread, SyncFuture> syncFuturesByHandler; + private final ThreadLocal<SyncFuture> cachedSyncFutures; /** * The highest known outstanding unsync'd WALEdit sequence number where sequence number is the @@ -569,8 +568,12 @@ public class FSHLog implements WAL { maxHandlersCount); this.disruptor.handleExceptionsWith(new RingBufferExceptionHandler()); this.disruptor.handleEventsWith(new RingBufferEventHandler [] {this.ringBufferEventHandler}); - // Presize our map of SyncFutures by handler objects. - this.syncFuturesByHandler = new ConcurrentHashMap<Thread, SyncFuture>(maxHandlersCount); + this.cachedSyncFutures = new ThreadLocal<SyncFuture>() { + @Override + protected SyncFuture initialValue() { + return new SyncFuture(); + } + }; // Starting up threads in constructor is a no no; Interface should have an init call. this.disruptor.start(); } @@ -1413,7 +1416,7 @@ public class FSHLog implements WAL { // SyncFuture reuse by thread, if TimeoutIOException happens, ringbuffer // still refer to it, so if this thread use it next time may get a wrong // result. - this.syncFuturesByHandler.remove(Thread.currentThread()); + this.cachedSyncFutures.remove(); throw tioe; } catch (InterruptedException ie) { LOG.warn("Interrupted", ie); @@ -1431,12 +1434,7 @@ public class FSHLog implements WAL { } private SyncFuture getSyncFuture(final long sequence, Span span) { - SyncFuture syncFuture = this.syncFuturesByHandler.get(Thread.currentThread()); - if (syncFuture == null) { - syncFuture = new SyncFuture(); - this.syncFuturesByHandler.put(Thread.currentThread(), syncFuture); - } - return syncFuture.reset(sequence, span); + return cachedSyncFutures.get().reset(sequence); } private void postSync(final long timeInNanos, final int handlerSyncs) {
