| // 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 java.io.OutputStream; |
| import java.io.PrintStream; |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.MemoryUsage; |
| |
| /** |
| * Blaze memory profiler. |
| * |
| * <p>At each call to {@code profile} performs garbage collection and stores |
| * heap and non-heap memory usage in an external file. |
| * |
| * <p><em>Heap memory</em> is the runtime data area from which memory for all |
| * class instances and arrays is allocated. <em>Non-heap memory</em> 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 |
| * <em>native heap</em>. |
| * |
| * <p>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; |
| |
| public synchronized void start(OutputStream out) { |
| this.memoryProfile = (out == null) ? null : new PrintStream(out); |
| this.currentPhase = ProfilePhase.INIT; |
| } |
| |
| public synchronized void stop() { |
| if (memoryProfile != null) { |
| memoryProfile.close(); |
| memoryProfile = null; |
| } |
| } |
| |
| public synchronized void markPhase(ProfilePhase nextPhase) { |
| if (memoryProfile != null) { |
| String name = currentPhase.description; |
| ManagementFactory.getMemoryMXBean().gc(); |
| MemoryUsage memoryUsage = ManagementFactory.getMemoryMXBean().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()); |
| |
| memoryUsage = ManagementFactory.getMemoryMXBean().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; |
| } |
| } |
| } |