aboutsummaryrefslogtreecommitdiff
path: root/sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java
diff options
context:
space:
mode:
Diffstat (limited to 'sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java')
-rw-r--r--sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java64
1 files changed, 64 insertions, 0 deletions
diff --git a/sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java b/sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java
new file mode 100644
index 0000000000..fb8141a905
--- /dev/null
+++ b/sql/hive-thriftserver/src/main/java/org/apache/hive/service/server/ThreadFactoryWithGarbageCleanup.java
@@ -0,0 +1,64 @@
+/**
+ * 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.hive.service.server;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ThreadFactory;
+
+import org.apache.hadoop.hive.metastore.RawStore;
+
+/**
+ * A ThreadFactory for constructing new HiveServer2 threads that lets you plug
+ * in custom cleanup code to be called before this thread is GC-ed.
+ * Currently cleans up the following:
+ * 1. ThreadLocal RawStore object:
+ * In case of an embedded metastore, HiveServer2 threads (foreground & background)
+ * end up caching a ThreadLocal RawStore object. The ThreadLocal RawStore object has
+ * an instance of PersistenceManagerFactory & PersistenceManager.
+ * The PersistenceManagerFactory keeps a cache of PersistenceManager objects,
+ * which are only removed when PersistenceManager#close method is called.
+ * HiveServer2 uses ExecutorService for managing thread pools for foreground & background threads.
+ * ExecutorService unfortunately does not provide any hooks to be called,
+ * when a thread from the pool is terminated.
+ * As a solution, we're using this ThreadFactory to keep a cache of RawStore objects per thread.
+ * And we are doing clean shutdown in the finalizer for each thread.
+ */
+public class ThreadFactoryWithGarbageCleanup implements ThreadFactory {
+
+ private static Map<Long, RawStore> threadRawStoreMap = new ConcurrentHashMap<Long, RawStore>();
+
+ private final String namePrefix;
+
+ public ThreadFactoryWithGarbageCleanup(String threadPoolName) {
+ namePrefix = threadPoolName;
+ }
+
+ @Override
+ public Thread newThread(Runnable runnable) {
+ Thread newThread = new ThreadWithGarbageCleanup(runnable);
+ newThread.setName(namePrefix + ": Thread-" + newThread.getId());
+ return newThread;
+ }
+
+ public static Map<Long, RawStore> getThreadRawStoreMap() {
+ return threadRawStoreMap;
+ }
+}