Author: llu
Date: Fri Aug 12 16:57:23 2011
New Revision: 1157187
URL: http://svn.apache.org/viewvc?rev=1157187&view=rev
Log:
HADOOP-7529. Fix lock cycles in metrics system. (llu)
Modified:
hadoop/common/trunk/hadoop-common/CHANGES.txt
hadoop/common/trunk/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/DefaultMetricsSystem.java
Modified: hadoop/common/trunk/hadoop-common/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-common/CHANGES.txt?rev=1157187&r1=1157186&r2=1157187&view=diff
==============================================================================
--- hadoop/common/trunk/hadoop-common/CHANGES.txt (original)
+++ hadoop/common/trunk/hadoop-common/CHANGES.txt Fri Aug 12 16:57:23 2011
@@ -493,6 +493,8 @@ Trunk (unreleased changes)
HADOOP-6622. Token should not print the password in toString. (eli)
+ HADOOP-7529. Fix lock cycles in metrics system. (llu)
+
Release 0.22.0 - Unreleased
INCOMPATIBLE CHANGES
Modified:
hadoop/common/trunk/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/DefaultMetricsSystem.java
URL:
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/DefaultMetricsSystem.java?rev=1157187&r1=1157186&r2=1157187&view=diff
==============================================================================
---
hadoop/common/trunk/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/DefaultMetricsSystem.java
(original)
+++
hadoop/common/trunk/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/DefaultMetricsSystem.java
Fri Aug 12 16:57:23 2011
@@ -18,6 +18,7 @@
package org.apache.hadoop.metrics2.lib;
+import java.util.concurrent.atomic.AtomicReference;
import javax.management.ObjectName;
import org.apache.hadoop.classification.InterfaceAudience;
@@ -34,7 +35,8 @@ import org.apache.hadoop.metrics2.impl.M
public enum DefaultMetricsSystem {
INSTANCE; // the singleton
- private MetricsSystem impl = new MetricsSystemImpl();
+ private AtomicReference<MetricsSystem> impl =
+ new AtomicReference<MetricsSystem>(new MetricsSystemImpl());
volatile boolean miniClusterMode = false;
final UniqueNames mBeanNames = new UniqueNames();
final UniqueNames sourceNames = new UniqueNames();
@@ -48,8 +50,8 @@ public enum DefaultMetricsSystem {
return INSTANCE.init(prefix);
}
- synchronized MetricsSystem init(String prefix) {
- return impl.init(prefix);
+ MetricsSystem init(String prefix) {
+ return impl.get().init(prefix);
}
/**
@@ -66,8 +68,9 @@ public enum DefaultMetricsSystem {
INSTANCE.shutdownInstance();
}
- synchronized void shutdownInstance() {
- if (impl.shutdown()) {
+ void shutdownInstance() {
+ boolean last = impl.get().shutdown();
+ if (last) synchronized(this) {
mBeanNames.map.clear();
sourceNames.map.clear();
}
@@ -78,13 +81,11 @@ public enum DefaultMetricsSystem {
return INSTANCE.setImpl(ms);
}
- synchronized MetricsSystem setImpl(MetricsSystem ms) {
- MetricsSystem old = impl;
- impl = ms;
- return old;
+ MetricsSystem setImpl(MetricsSystem ms) {
+ return impl.getAndSet(ms);
}
- synchronized MetricsSystem getImpl() { return impl; }
+ MetricsSystem getImpl() { return impl.get(); }
@InterfaceAudience.Private
public static void setMiniClusterMode(boolean choice) {
