HDFS-5776 Support 'hedged' reads in DFSClient

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1571467 13f79535-47bb-0310-9956-ffa450edef68
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Michael Stack 2014-02-24 22:34:55 +00:00
parent 17db74a1c1
commit 036af54387
1 changed files with 55 additions and 0 deletions

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/**
* 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
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs;
import java.util.concurrent.atomic.AtomicLong;
/**
* The client-side metrics for hedged read feature.
* This class has a number of metrics variables that are publicly accessible,
* we can grab them from client side, like HBase.
*/
public class DFSHedgedReadMetrics {
public AtomicLong hedgedReadOps = new AtomicLong();
public AtomicLong hedgedReadOpsWin = new AtomicLong();
public AtomicLong hedgedReadOpsInCurThread = new AtomicLong();
public void incHedgedReadOps() {
hedgedReadOps.incrementAndGet();
}
public void incHedgedReadOpsInCurThread() {
hedgedReadOpsInCurThread.incrementAndGet();
}
public void incHedgedReadWins() {
hedgedReadOpsWin.incrementAndGet();
}
public long getHedgedReadOps() {
return hedgedReadOps.longValue();
}
public long getHedgedReadOpsInCurThread() {
return hedgedReadOpsInCurThread.longValue();
}
public long getHedgedReadWins() {
return hedgedReadOpsWin.longValue();
}
}