| // Copyright 2018 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.base.Preconditions; |
| import com.google.common.base.Stopwatch; |
| import com.sun.management.OperatingSystemMXBean; |
| import java.lang.management.ManagementFactory; |
| import java.time.Duration; |
| import java.util.concurrent.TimeUnit; |
| |
| /** Thread to collect local cpu usage data and log into JSON profile. */ |
| public class CollectLocalCpuUsage extends Thread { |
| // TODO(twerth): Make these configurable. |
| private static final Duration BUCKET_DURATION = Duration.ofSeconds(1); |
| private static final long LOCAL_CPU_SLEEP_MILLIS = 200; |
| |
| private volatile boolean stopCpuUsage; |
| private volatile boolean profilingStarted; |
| private TimeSeries localCpuUsage; |
| private Stopwatch stopwatch; |
| |
| @Override |
| public void run() { |
| stopwatch = Stopwatch.createStarted(); |
| localCpuUsage = |
| new TimeSeries( |
| /* startTimeMillis= */ stopwatch.elapsed().toMillis(), BUCKET_DURATION.toMillis()); |
| OperatingSystemMXBean bean = |
| (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean(); |
| Duration previousElapsed = stopwatch.elapsed(); |
| long previousCpuTimeNanos = bean.getProcessCpuTime(); |
| profilingStarted = true; |
| while (!stopCpuUsage) { |
| try { |
| Thread.sleep(LOCAL_CPU_SLEEP_MILLIS); |
| } catch (InterruptedException e) { |
| return; |
| } |
| Duration nextElapsed = stopwatch.elapsed(); |
| long nextCpuTimeNanos = bean.getProcessCpuTime(); |
| double deltaNanos = nextElapsed.minus(previousElapsed).toNanos(); |
| double cpuLevel = (nextCpuTimeNanos - previousCpuTimeNanos) / deltaNanos; |
| localCpuUsage.addRange(previousElapsed.toMillis(), nextElapsed.toMillis(), cpuLevel); |
| previousElapsed = nextElapsed; |
| previousCpuTimeNanos = nextCpuTimeNanos; |
| } |
| } |
| |
| public void stopCollecting() { |
| Preconditions.checkArgument(!stopCpuUsage); |
| stopCpuUsage = true; |
| interrupt(); |
| } |
| |
| public void logCollectedData() { |
| if (!profilingStarted) { |
| return; |
| } |
| Preconditions.checkArgument(stopCpuUsage); |
| long endTimeNanos = System.nanoTime(); |
| long elapsedNanos = stopwatch.elapsed(TimeUnit.NANOSECONDS); |
| long startTimeNanos = endTimeNanos - elapsedNanos; |
| int len = (int) (elapsedNanos / BUCKET_DURATION.toNanos()) + 1; |
| double[] localCpuUsageValues = localCpuUsage.toDoubleArray(len); |
| Profiler profiler = Profiler.instance(); |
| for (int i = 0; i < len; i++) { |
| long eventTimeNanos = startTimeNanos + i * BUCKET_DURATION.toNanos(); |
| profiler.logEventAtTime( |
| eventTimeNanos, ProfilerTask.LOCAL_CPU_USAGE, String.valueOf(localCpuUsageValues[i])); |
| } |
| localCpuUsage = null; |
| } |
| } |