// Copyright 2014 The Bazel Authors. All rights reserved. // // Licensed 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 com.google.devtools.build.lib.profiler; import com.google.common.annotations.VisibleForTesting; import com.google.common.base.Splitter; import com.google.devtools.common.options.OptionsParsingException; import java.io.OutputStream; import java.io.PrintStream; import java.lang.management.ManagementFactory; import java.lang.management.MemoryMXBean; import java.lang.management.MemoryUsage; import java.time.Duration; import java.util.Iterator; import java.util.NoSuchElementException; import javax.annotation.Nullable; /** * Blaze memory profiler. * *
At each call to {@code profile} performs garbage collection and stores * heap and non-heap memory usage in an external file. * *
Heap memory is the runtime data area from which memory for all * class instances and arrays is allocated. Non-heap memory includes * the method area and memory required for the internal processing or * optimization of the JVM. It stores per-class structures such as a runtime * constant pool, field and method data, and the code for methods and * constructors. The Java Native Interface (JNI) code or the native library of * an application and the JVM implementation allocate memory from the * native heap. * *
The script in /devtools/blaze/scripts/blaze-memchart.sh can be used for post processing.
*/
public final class MemoryProfiler {
private static final MemoryProfiler INSTANCE = new MemoryProfiler();
public static MemoryProfiler instance() {
return INSTANCE;
}
private PrintStream memoryProfile;
private ProfilePhase currentPhase;
private long heapUsedMemoryAtFinish;
@Nullable private MemoryProfileStableHeapParameters memoryProfileStableHeapParameters;
public synchronized void setStableMemoryParameters(
MemoryProfileStableHeapParameters memoryProfileStableHeapParameters) {
this.memoryProfileStableHeapParameters = memoryProfileStableHeapParameters;
}
public synchronized void start(OutputStream out) {
this.memoryProfile = (out == null) ? null : new PrintStream(out);
this.currentPhase = ProfilePhase.INIT;
heapUsedMemoryAtFinish = 0;
}
public synchronized void stop() {
if (memoryProfile != null) {
memoryProfile.close();
memoryProfile = null;
}
heapUsedMemoryAtFinish = 0;
}
public synchronized long getHeapUsedMemoryAtFinish() {
return heapUsedMemoryAtFinish;
}
public synchronized void markPhase(ProfilePhase nextPhase) throws InterruptedException {
if (memoryProfile != null) {
MemoryMXBean bean = ManagementFactory.getMemoryMXBean();
prepareBean(nextPhase, bean, (duration) -> Thread.sleep(duration.toMillis()));
String name = currentPhase.description;
MemoryUsage memoryUsage = bean.getHeapMemoryUsage();
memoryProfile.println(name + ":heap:init:" + memoryUsage.getInit());
memoryProfile.println(name + ":heap:used:" + memoryUsage.getUsed());
memoryProfile.println(name + ":heap:commited:" + memoryUsage.getCommitted());
memoryProfile.println(name + ":heap:max:" + memoryUsage.getMax());
if (nextPhase == ProfilePhase.FINISH) {
heapUsedMemoryAtFinish = memoryUsage.getUsed();
}
memoryUsage = bean.getNonHeapMemoryUsage();
memoryProfile.println(name + ":non-heap:init:" + memoryUsage.getInit());
memoryProfile.println(name + ":non-heap:used:" + memoryUsage.getUsed());
memoryProfile.println(name + ":non-heap:commited:" + memoryUsage.getCommitted());
memoryProfile.println(name + ":non-heap:max:" + memoryUsage.getMax());
currentPhase = nextPhase;
}
}
@VisibleForTesting
synchronized void prepareBean(ProfilePhase nextPhase, MemoryMXBean bean, Sleeper sleeper)
throws InterruptedException {
bean.gc();
if (nextPhase == ProfilePhase.FINISH && memoryProfileStableHeapParameters != null) {
for (int i = 1; i < memoryProfileStableHeapParameters.numTimesToDoGc; i++) {
sleeper.sleep(memoryProfileStableHeapParameters.timeToSleepBetweenGcs);
bean.gc();
}
}
}
/**
* Parameters that control how {@code MemoryProfiler} tries to get a stable heap at the end of the
* build.
*/
public static class MemoryProfileStableHeapParameters {
private final int numTimesToDoGc;
private final Duration timeToSleepBetweenGcs;
private MemoryProfileStableHeapParameters(int numTimesToDoGc, Duration timeToSleepBetweenGcs) {
this.numTimesToDoGc = numTimesToDoGc;
this.timeToSleepBetweenGcs = timeToSleepBetweenGcs;
}
/** Converter for {@code MemoryProfileStableHeapParameters} option. */
public static class Converter
implements com.google.devtools.common.options.Converter