1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.textclassifier.common; 18 19 import com.android.textclassifier.common.base.TcLog; 20 import com.google.common.util.concurrent.ListeningExecutorService; 21 import com.google.common.util.concurrent.MoreExecutors; 22 import com.google.common.util.concurrent.ThreadFactoryBuilder; 23 import java.util.concurrent.Executors; 24 25 // TODO(licha): Revisit the configurations of thread pools 26 /** 27 * Holder of executor singletons. 28 * 29 * <p>Note because we have two processes, so we may keep two copis of executors in this class. 30 */ 31 public final class TextClassifierServiceExecutors { 32 private static final String TAG = "TextClassifierServiceExecutors"; 33 34 /** Returns an executor with normal priority. Used for handling client requests. */ getNormhPriorityExecutor()35 public static ListeningExecutorService getNormhPriorityExecutor() { 36 return NormPriorityExecutorHolder.normPriorityExecutor; 37 } 38 39 /** Returns a single-thread executor with low priority. Used for internal tasks like logging. */ getLowPriorityExecutor()40 public static ListeningExecutorService getLowPriorityExecutor() { 41 return LowPriorityExecutorHolder.lowPriorityExecutor; 42 } 43 44 /** 45 * Returns a single-thread executor with min priority. Used for downloader background processing. 46 */ getDownloaderExecutor()47 public static ListeningExecutorService getDownloaderExecutor() { 48 return DownloaderExecutorHolder.downloaderExecutor; 49 } 50 51 /** 52 * Returns a single-thread executor with min priority for network IO ops. Currently only used by 53 * model downloader service. 54 */ getNetworkIOExecutor()55 public static ListeningExecutorService getNetworkIOExecutor() { 56 return NetworkIOExecutorHolder.networkIOExecutor; 57 } 58 59 private static class NormPriorityExecutorHolder { 60 static final ListeningExecutorService normPriorityExecutor = 61 init("tcs-norm-prio-executor-%d", Thread.NORM_PRIORITY, /* corePoolSize= */ 2); 62 } 63 64 private static class LowPriorityExecutorHolder { 65 static final ListeningExecutorService lowPriorityExecutor = 66 init("tcs-low-prio-executor-%d", Thread.NORM_PRIORITY - 1, /* corePoolSize= */ 1); 67 } 68 69 private static class DownloaderExecutorHolder { 70 static final ListeningExecutorService downloaderExecutor = 71 init("tcs-download-executor-%d", Thread.MIN_PRIORITY, /* corePoolSize= */ 1); 72 } 73 74 private static class NetworkIOExecutorHolder { 75 static final ListeningExecutorService networkIOExecutor = 76 init("tcs-network-io-executor-%d", Thread.MIN_PRIORITY, /* corePoolSize= */ 1); 77 } 78 init(String nameFormat, int priority, int corePoolSize)79 private static ListeningExecutorService init(String nameFormat, int priority, int corePoolSize) { 80 TcLog.v(TAG, "Creating executor: " + nameFormat); 81 return MoreExecutors.listeningDecorator( 82 Executors.newFixedThreadPool( 83 corePoolSize, 84 new ThreadFactoryBuilder() 85 .setNameFormat(nameFormat) 86 .setPriority(priority) 87 // In Android, those uncaught exceptions will crash the whole process if not handled 88 .setUncaughtExceptionHandler( 89 (thread, throwable) -> 90 TcLog.e(TAG, "Exception from executor: " + thread, throwable)) 91 .build())); 92 } 93 TextClassifierServiceExecutors()94 private TextClassifierServiceExecutors() {} 95 } 96