/*
* The MIT License
*
* Copyright 2010 Sony Ericsson Mobile Communications. All rights reserved.
* Copyright 2013 Sony Mobile Communications AB. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.sonymobile.tools.gerrit.gerritevents;
import com.sonymobile.tools.gerrit.gerritevents.workers.GerritWorkersConfig;
import com.sonymobile.tools.gerrit.gerritevents.workers.cmd.AbstractSendCommandJob;
import com.sonymobile.tools.gerrit.gerritevents.workers.cmd.AbstractSendCommandJob2;
import com.sonymobile.tools.gerrit.gerritevents.workers.rest.AbstractRestCommandJob;
import com.sonymobile.tools.gerrit.gerritevents.workers.rest.AbstractRestCommandJob2;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.concurrent.Callable;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
/**
* A thread-pool and queue implementation for queueing commands to the Gerrit server.
*
* @author Robert Sandell <robert.sandell@sonyericsson.com>
*/
public final class GerritSendCommandQueue {
private static final Logger logger = LoggerFactory.getLogger(GerritSendCommandQueue.class);
private static GerritSendCommandQueue instance;
private ThreadPoolExecutor executor = null;
private static final String THREAD_PREFIX = "Gerrit-send-command-thread-";
private static final int THREAD_KEEP_ALIVE_TIME = 20;
/**
* The minimum size of the job-queue before monitors should begin to warn the administrator(s).
*/
public static final int SEND_QUEUE_SIZE_WARNING_THRESHOLD = 20;
private static final int WAIT_FOR_JOBS_SHUTDOWN_TIMEOUT = 30;
/**
* Private Default constructor.
*/
private GerritSendCommandQueue() {
}
/**
* Returns the singleton instance of the command-queue.
*
* @return the instance.
*/
public static GerritSendCommandQueue getInstance() {
if (instance == null) {
throw new IllegalStateException("Need to initialize the instance first!");
}
return instance;
}
/**
* Adds a command-job to the singleton instance's queue.
*
* @param job the job to do.
*/
public static void queue(AbstractSendCommandJob job) {
getInstance().queueJob(job);
}
/**
* Adds a command-job to the singleton instance's queue.
*
* @param job the job to do.
*/
public static void queue(AbstractRestCommandJob job) {
getInstance().queueJob(job);
}
/**
* Adds a command-job to the singleton instance's queue.
*
* @param job the job to do.
*/
public static void queue(AbstractSendCommandJob2 job) {
getInstance().queueJob(job);
}
/**
* Adds a command-job to the singleton instance's queue.
*
* @param job the job to do.
*/
public static void queue(AbstractRestCommandJob2 job) {
getInstance().queueJob(job);
}
/**
* Returns the current queue size.
*
* @return the queue size,
* @see java.util.concurrent.ThreadPoolExecutor#getQueue()
*/
public static int getQueueSize() {
if (instance != null && instance.executor != null) {
return instance.executor.getQueue().size();
} else {
return 0;
}
}
/**
* Adds a job to the queue.
* At the same time tries to update the thread-pool size from the latest config of the job.
*
* @param job the job to do.
* @see java.util.concurrent.ThreadPoolExecutor#submit(Runnable)
*/
public void queueJob(Runnable job) {
try {
logger.debug("Queueing job {}", job);
executor.submit(job);
} catch (RejectedExecutionException e) {
logger.error("Unable to queue a send-command-job! ", e);
}
checkQueueSize();
}
/**
* Adds a job to the queue.
* At the same time tries to update the thread-pool size from the latest config of the job.
*
* @param job the job to do.
* @return the future object.
* @see java.util.concurrent.ThreadPoolExecutor#submit(Runnable)
*/
public Future<String> queueJob(Callable<String> job) {
Future<String> future = null;
try {
logger.debug("Queueing job {}", job);
future = executor.submit(job);
} catch (RejectedExecutionException e) {
logger.error("Unable to queue a send-command-job! ", e);
}
checkQueueSize();
return future;
}
/**
* Checks queue size.
*/
private void checkQueueSize() {
int queueSize = getQueueSize();
if (queueSize >= SEND_QUEUE_SIZE_WARNING_THRESHOLD) {
logger.warn("The Gerrit-trigger send commands queue contains {} items!"
+ " Something might be stuck, or your system can't process the commands fast enough."
+ " Try to increase the number of sending worker threads on the Gerrit configuration page."
+ " Current thread-pool size: {}",
queueSize, executor.getPoolSize());
logger.info("Nr of active pool-threads: {}", executor.getActiveCount());
}
}
/**
* Starts the executor if it hasn't started yet, or updates the thread-pool size if it is started.
*
* @param config the config with the pool-size.
*/
protected void startQueue(GerritWorkersConfig config) {
if (executor == null) {
logger.debug("Starting the sending thread pool.");
executor = new ThreadPoolExecutor(
config.getNumberOfSendingWorkerThreads(),
config.getNumberOfSendingWorkerThreads(),
THREAD_KEEP_ALIVE_TIME, TimeUnit.MINUTES,
new LinkedBlockingQueue<Runnable>(),
new ThreadFactory() {
private final ThreadFactory parent = Executors.defaultThreadFactory();
private final AtomicInteger tid = new AtomicInteger(1);
@Override
public Thread newThread(final Runnable task) {
final Thread t = parent.newThread(task);
t.setName(THREAD_PREFIX + tid.getAndIncrement());
return t;
}
});
executor.allowCoreThreadTimeOut(true);
//Start with one thread, and build it up gradually as it needs.
executor.prestartCoreThread();
logger.info("SendQueue started! Current pool size: {}", executor.getPoolSize());
} else {
if (executor.getCorePoolSize() < config.getNumberOfSendingWorkerThreads()) {
//If the number has increased we need to set the max first, or we'll get an IllegalArgumentException
executor.setMaximumPoolSize(config.getNumberOfSendingWorkerThreads());
executor.setCorePoolSize(config.getNumberOfSendingWorkerThreads());
} else if (executor.getCorePoolSize() > config.getNumberOfSendingWorkerThreads()) {
//If the number has decreased we need to set the core first.
executor.setCorePoolSize(config.getNumberOfSendingWorkerThreads());
executor.setMaximumPoolSize(config.getNumberOfSendingWorkerThreads());
}
logger.debug("SendQueue running. Current pool size: {}. Current Queue size: {}",
executor.getPoolSize(), getQueueSize());
logger.debug("Nr of active pool-threads: {}", executor.getActiveCount());
}
}
/**
* Initializes the singleton instance and configures it.
*
* @param config the configuration.
*/
public static synchronized void initialize(GerritWorkersConfig config) {
if (instance == null) {
instance = new GerritSendCommandQueue();
}
getInstance().startQueue(config);
}
/**
* Reconfigures the instance.
*
* @param config the config
*/
public static synchronized void configure(GerritWorkersConfig config) {
getInstance().startQueue(config);
}
/**
* Shuts down the executor(s).
* Gracefully waits for {@link #WAIT_FOR_JOBS_SHUTDOWN_TIMEOUT} seconds for all jobs to finish
* before forcefully shutting them down.
*/
public static void shutdown() {
if (instance != null && instance.executor != null) {
ThreadPoolExecutor pool = instance.executor;
instance.executor = null;
pool.shutdown(); // Disable new tasks from being submitted
try {
// Wait a while for existing tasks to terminate
if (!pool.awaitTermination(WAIT_FOR_JOBS_SHUTDOWN_TIMEOUT, TimeUnit.SECONDS)) {
pool.shutdownNow(); // Cancel currently executing tasks
// Wait a while for tasks to respond to being cancelled
if (!pool.awaitTermination(WAIT_FOR_JOBS_SHUTDOWN_TIMEOUT, TimeUnit.SECONDS)) {
logger.error("Pool did not terminate");
}
}
} catch (InterruptedException ie) {
// (Re-)Cancel if current thread also interrupted
pool.shutdownNow();
// Preserve interrupt status
Thread.currentThread().interrupt();
}
}
}
}