| // Copyright 2021 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.platform; |
| |
| import com.google.common.flogger.GoogleLogger; |
| import com.google.devtools.build.lib.events.Reporter; |
| import com.google.devtools.build.lib.jni.JniLoader; |
| import com.google.devtools.build.lib.runtime.BlazeModule; |
| import com.google.devtools.build.lib.runtime.CommandEnvironment; |
| import com.google.devtools.build.lib.util.OS; |
| import javax.annotation.Nullable; |
| import javax.annotation.concurrent.GuardedBy; |
| |
| /** Detects load advisory events. */ |
| public final class SystemLoadAdvisoryModule extends BlazeModule { |
| private static final GoogleLogger logger = GoogleLogger.forEnclosingClass(); |
| |
| static { |
| JniLoader.loadJni(); |
| } |
| |
| @GuardedBy("this") |
| @Nullable |
| private Reporter reporter; |
| |
| private native void registerJNI(); |
| |
| private static native int systemLoadAdvisory(); |
| |
| public SystemLoadAdvisoryModule() { |
| if (JniLoader.isJniAvailable()) { |
| registerJNI(); |
| } |
| } |
| |
| @Override |
| public synchronized void beforeCommand(CommandEnvironment env) { |
| this.reporter = env.getReporter(); |
| reportSystemLoadAdvisoryEvent(true, systemLoadAdvisory()); |
| } |
| |
| @Override |
| public synchronized void afterCommand() { |
| this.reporter = null; |
| } |
| |
| /** |
| * Callback that is called from the native system load advisory monitoring code. |
| * |
| * @param value - 0-100 |
| * <p>Intermediate values are platform dependent. |
| * <p>For macOS the system advisory states map to: |
| * <ul> |
| * <li>0 - kIOSystemLoadAdvisoryLevelGreat |
| * <li>25 - kIOSystemLoadAdvisoryLevelOK |
| * <li>75 - kIOSystemLoadAdvisoryLevelBad |
| * </ul> |
| */ |
| synchronized void systemLoadAdvisoryCallback(int value) { |
| reportSystemLoadAdvisoryEvent(false, value); |
| } |
| |
| private String macOSSystemLoadAdvisoryDescription(int value) { |
| switch (value) { |
| case 0: |
| return "Great"; |
| case 25: |
| return "OK"; |
| case 75: |
| return "Bad"; |
| default: |
| return "Unknown System Load Advisory Value: " + value; |
| } |
| } |
| |
| private synchronized void reportSystemLoadAdvisoryEvent(boolean isInitialValue, int value) { |
| String osDescription = "Unknown"; |
| if (OS.getCurrent() == OS.DARWIN) { |
| osDescription = macOSSystemLoadAdvisoryDescription(value); |
| } |
| SystemLoadAdvisoryEvent event = new SystemLoadAdvisoryEvent(value, osDescription); |
| String logString = event.logString(); |
| |
| if (value < 0 || value > 100) { |
| // values outside this range are not expected. |
| logger.atSevere().log("%s", logString); |
| } else if (value > 50) { |
| // 50 arbitrarily chosen as point where user is likely to be more concerned. |
| logger.atWarning().log("%s", logString); |
| } else if (!isInitialValue || value > 25) { |
| // Don't spam the logs if we have a Great or OK value at startup. |
| logger.atInfo().log("%s", logString); |
| } |
| if (reporter != null) { |
| reporter.post(event); |
| } |
| } |
| } |