Index: hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/CpuTimeTracker.java IDEA additional info: Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP <+>UTF-8 =================================================================== --- hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/CpuTimeTracker.java (revision c35510a465cbda72c08239bcb5537375478bec3a) +++ hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/CpuTimeTracker.java (revision fec26656ba2bdb7a26561ce309ed92b2418cb00a) @@ -97,7 +97,9 @@ * @param newTime new sample time */ public void updateElapsedJiffies(BigInteger elapsedJiffies, long newTime) { - cumulativeCpuTime = elapsedJiffies.multiply(jiffyLengthInMillis); + BigInteger newValue = elapsedJiffies.multiply(jiffyLengthInMillis); + cumulativeCpuTime = newValue.compareTo(cumulativeCpuTime) >= 0 ? + newValue : cumulativeCpuTime; sampleTime = newTime; } Index: hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestCpuTimeTracker.java IDEA additional info: Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP <+>UTF-8 =================================================================== --- hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestCpuTimeTracker.java (revision fec26656ba2bdb7a26561ce309ed92b2418cb00a) +++ hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestCpuTimeTracker.java (revision fec26656ba2bdb7a26561ce309ed92b2418cb00a) @@ -0,0 +1,55 @@ +/** + * 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.util; + +import org.junit.Test; +import java.math.BigInteger; +import static org.junit.Assert.assertTrue; + +public class TestCpuTimeTracker { + @Test + public void test() throws InterruptedException { + CpuTimeTracker tracker = new CpuTimeTracker(10); + tracker.updateElapsedJiffies( + BigInteger.valueOf(100), + System.currentTimeMillis()); + float val1 = tracker.getCpuTrackerUsagePercent(); + assertTrue( + "Not invalid CPU usage", + val1 == -1.0); + Thread.sleep(1000); + tracker.updateElapsedJiffies( + BigInteger.valueOf(200), + System.currentTimeMillis()); + float val2 = tracker.getCpuTrackerUsagePercent(); + assertTrue( + "Not positive CPU usage", + val2 > 0); + Thread.sleep(1000); + tracker.updateElapsedJiffies( + BigInteger.valueOf(0), + System.currentTimeMillis()); + float val3 = tracker.getCpuTrackerUsagePercent(); + assertTrue( + "Not positive CPU usage", + val3 == 0.0); + } +} + + +