bharathv commented on a change in pull request #3371: URL: https://github.com/apache/hbase/pull/3371#discussion_r650613715
########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SyncFutureCache.java ########## @@ -0,0 +1,80 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.hadoop.hbase.regionserver.wal; + +import java.util.concurrent.TimeUnit; +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.hbase.HConstants; +import org.apache.yetus.audience.InterfaceAudience; +import org.apache.hbase.thirdparty.com.google.common.cache.Cache; +import org.apache.hbase.thirdparty.com.google.common.cache.CacheBuilder; + +/** + * A cache of {@link SyncFuture}s. This class supports two methods + * {@link SyncFutureCache#getIfPresentOrNew()} and {@link SyncFutureCache#offer()}. + * + * Usage pattern: + * SyncFuture sf = syncFutureCache.getIfPresentOrNew(); + * sf.reset(...); + * // Use the sync future + * finally: syncFutureCache.offer(sf); + * + * Offering the sync future back to the cache makes it eligible for reuse within the same thread + * context. Cache keyed by the accessing thread instance and automatically invalidated if it remains + * unused for {@link SyncFutureCache#SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS} minutes. + */ +@InterfaceAudience.Private +public final class SyncFutureCache { + + private final long SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS = 2; + + private final Cache<Thread, SyncFuture> syncFutureCache; + + public SyncFutureCache(final Configuration conf) { + final int handlerCount = conf.getInt(HConstants.REGION_SERVER_HANDLER_COUNT, + HConstants.DEFAULT_REGION_SERVER_HANDLER_COUNT); + syncFutureCache = CacheBuilder.newBuilder().initialCapacity(handlerCount) Review comment: We don't need a putIfAbsent() either, switched to put() as we are ok with the overwrites here, it doesn't show up in the profiler now. Ya we can't use the > I'm not sure if there is a benefit over a ThreadLocal in your case. Right, we can't use TL here because of the bug, but WeakKey cache seems like a good alternative, thanks for the pointer. ########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SyncFutureCache.java ########## @@ -0,0 +1,80 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.hadoop.hbase.regionserver.wal; + +import java.util.concurrent.TimeUnit; +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.hbase.HConstants; +import org.apache.yetus.audience.InterfaceAudience; +import org.apache.hbase.thirdparty.com.google.common.cache.Cache; +import org.apache.hbase.thirdparty.com.google.common.cache.CacheBuilder; + +/** + * A cache of {@link SyncFuture}s. This class supports two methods + * {@link SyncFutureCache#getIfPresentOrNew()} and {@link SyncFutureCache#offer()}. + * + * Usage pattern: + * SyncFuture sf = syncFutureCache.getIfPresentOrNew(); + * sf.reset(...); + * // Use the sync future + * finally: syncFutureCache.offer(sf); + * + * Offering the sync future back to the cache makes it eligible for reuse within the same thread + * context. Cache keyed by the accessing thread instance and automatically invalidated if it remains + * unused for {@link SyncFutureCache#SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS} minutes. + */ +@InterfaceAudience.Private +public final class SyncFutureCache { + + private final long SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS = 2; + + private final Cache<Thread, SyncFuture> syncFutureCache; + + public SyncFutureCache(final Configuration conf) { + final int handlerCount = conf.getInt(HConstants.REGION_SERVER_HANDLER_COUNT, + HConstants.DEFAULT_REGION_SERVER_HANDLER_COUNT); + syncFutureCache = CacheBuilder.newBuilder().initialCapacity(handlerCount) + .expireAfterWrite(SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS, TimeUnit.MINUTES).build(); + } + + public SyncFuture getIfPresentOrNew() { + final SyncFuture[] result = {null}; + // Invalidate the entry if a mapping exists. We do not want it to be reused at the same time. + syncFutureCache.asMap().compute(Thread.currentThread(), (thread, syncFuture) -> { + result[0] = syncFuture; + return null; + }); + if (result[0] != null) { + return result[0]; + } + return new SyncFuture(); + } + + /** + * Offers the sync future back to the cache for reuse. + */ + public void offer(SyncFuture syncFuture) { + syncFutureCache.asMap().putIfAbsent(syncFuture.getThread(), syncFuture); + } + + public void cleanUp() { + if (syncFutureCache != null) { + syncFutureCache.invalidateAll(); + } + } Review comment: Makes sense, done. ########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SyncFutureCache.java ########## @@ -0,0 +1,80 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.hadoop.hbase.regionserver.wal; + +import java.util.concurrent.TimeUnit; +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.hbase.HConstants; +import org.apache.yetus.audience.InterfaceAudience; +import org.apache.hbase.thirdparty.com.google.common.cache.Cache; +import org.apache.hbase.thirdparty.com.google.common.cache.CacheBuilder; + +/** + * A cache of {@link SyncFuture}s. This class supports two methods + * {@link SyncFutureCache#getIfPresentOrNew()} and {@link SyncFutureCache#offer()}. + * + * Usage pattern: + * SyncFuture sf = syncFutureCache.getIfPresentOrNew(); + * sf.reset(...); + * // Use the sync future + * finally: syncFutureCache.offer(sf); + * + * Offering the sync future back to the cache makes it eligible for reuse within the same thread + * context. Cache keyed by the accessing thread instance and automatically invalidated if it remains + * unused for {@link SyncFutureCache#SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS} minutes. + */ +@InterfaceAudience.Private +public final class SyncFutureCache { + + private final long SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS = 2; + + private final Cache<Thread, SyncFuture> syncFutureCache; + + public SyncFutureCache(final Configuration conf) { + final int handlerCount = conf.getInt(HConstants.REGION_SERVER_HANDLER_COUNT, + HConstants.DEFAULT_REGION_SERVER_HANDLER_COUNT); + syncFutureCache = CacheBuilder.newBuilder().initialCapacity(handlerCount) + .expireAfterWrite(SYNC_FUTURE_INVALIDATION_TIMEOUT_MINS, TimeUnit.MINUTES).build(); + } + + public SyncFuture getIfPresentOrNew() { + final SyncFuture[] result = {null}; + // Invalidate the entry if a mapping exists. We do not want it to be reused at the same time. + syncFutureCache.asMap().compute(Thread.currentThread(), (thread, syncFuture) -> { + result[0] = syncFuture; + return null; + }); Review comment: Neat, done! -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
