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/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you 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 org.elasticsearch.threadpool;
import org.apache.logging.log4j.message.ParameterizedMessage;
import org.apache.logging.log4j.util.Supplier;
import org.apache.lucene.util.Counter;
import org.apache.lucene.util.IOUtils;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.component.AbstractComponent;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.io.stream.Writeable;
import org.elasticsearch.common.settings.Setting;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.unit.SizeValue;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.util.concurrent.AbstractRunnable;
import org.elasticsearch.common.util.concurrent.EsAbortPolicy;
import org.elasticsearch.common.util.concurrent.EsExecutors;
import org.elasticsearch.common.util.concurrent.EsRejectedExecutionException;
import org.elasticsearch.common.util.concurrent.EsThreadPoolExecutor;
import org.elasticsearch.common.util.concurrent.ThreadContext;
import org.elasticsearch.common.util.concurrent.XRejectedExecutionHandler;
import org.elasticsearch.common.xcontent.ToXContent;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.node.Node;
import java.io.Closeable;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import static java.util.Collections.unmodifiableMap;
public class ThreadPool extends AbstractComponent implements Closeable {
public static class Names {
public static final String SAME = "same";
public static final String GENERIC = "generic";
public static final String LISTENER = "listener";
public static final String GET = "get";
public static final String INDEX = "index";
public static final String BULK = "bulk";
public static final String SEARCH = "search";
public static final String MANAGEMENT = "management";
public static final String FLUSH = "flush";
public static final String REFRESH = "refresh";
public static final String WARMER = "warmer";
public static final String SNAPSHOT = "snapshot";
public static final String FORCE_MERGE = "force_merge";
public static final String FETCH_SHARD_STARTED = "fetch_shard_started";
public static final String FETCH_SHARD_STORE = "fetch_shard_store";
}
public enum ThreadPoolType {
DIRECT("direct"),
FIXED("fixed"),
SCALING("scaling");
private final String type;
public String getType() {
return type;
}
ThreadPoolType(String type) {
this.type = type;
}
private static final Map TYPE_MAP;
static {
Map typeMap = new HashMap<>();
for (ThreadPoolType threadPoolType : ThreadPoolType.values()) {
typeMap.put(threadPoolType.getType(), threadPoolType);
}
TYPE_MAP = Collections.unmodifiableMap(typeMap);
}
public static ThreadPoolType fromType(String type) {
ThreadPoolType threadPoolType = TYPE_MAP.get(type);
if (threadPoolType == null) {
throw new IllegalArgumentException("no ThreadPoolType for " + type);
}
return threadPoolType;
}
}
public static final Map THREAD_POOL_TYPES;
static {
HashMap map = new HashMap<>();
map.put(Names.SAME, ThreadPoolType.DIRECT);
map.put(Names.GENERIC, ThreadPoolType.SCALING);
map.put(Names.LISTENER, ThreadPoolType.FIXED);
map.put(Names.GET, ThreadPoolType.FIXED);
map.put(Names.INDEX, ThreadPoolType.FIXED);
map.put(Names.BULK, ThreadPoolType.FIXED);
map.put(Names.SEARCH, ThreadPoolType.FIXED);
map.put(Names.MANAGEMENT, ThreadPoolType.SCALING);
map.put(Names.FLUSH, ThreadPoolType.SCALING);
map.put(Names.REFRESH, ThreadPoolType.SCALING);
map.put(Names.WARMER, ThreadPoolType.SCALING);
map.put(Names.SNAPSHOT, ThreadPoolType.SCALING);
map.put(Names.FORCE_MERGE, ThreadPoolType.FIXED);
map.put(Names.FETCH_SHARD_STARTED, ThreadPoolType.SCALING);
map.put(Names.FETCH_SHARD_STORE, ThreadPoolType.SCALING);
THREAD_POOL_TYPES = Collections.unmodifiableMap(map);
}
private Map executors = new HashMap<>();
private final ScheduledThreadPoolExecutor scheduler;
private final CachedTimeThread cachedTimeThread;
static final ExecutorService DIRECT_EXECUTOR = EsExecutors.newDirectExecutorService();
private final ThreadContext threadContext;
private final Map builders;
public Collection builders() {
return Collections.unmodifiableCollection(builders.values());
}
public static Setting ESTIMATED_TIME_INTERVAL_SETTING =
Setting.timeSetting("thread_pool.estimated_time_interval", TimeValue.timeValueMillis(200), Setting.Property.NodeScope);
public ThreadPool(final Settings settings, final ExecutorBuilder... customBuilders) {
super(settings);
assert Node.NODE_NAME_SETTING.exists(settings);
final Map builders = new HashMap<>();
final int availableProcessors = EsExecutors.boundedNumberOfProcessors(settings);
final int halfProcMaxAt5 = halfNumberOfProcessorsMaxFive(availableProcessors);
final int halfProcMaxAt10 = halfNumberOfProcessorsMaxTen(availableProcessors);
final int genericThreadPoolMax = boundedBy(4 * availableProcessors, 128, 512);
builders.put(Names.GENERIC, new ScalingExecutorBuilder(Names.GENERIC, 4, genericThreadPoolMax, TimeValue.timeValueSeconds(30)));
builders.put(Names.INDEX, new FixedExecutorBuilder(settings, Names.INDEX, availableProcessors, 200));
builders.put(Names.BULK, new FixedExecutorBuilder(settings, Names.BULK, availableProcessors, 200)); // now that we reuse bulk for index/delete ops
builders.put(Names.GET, new FixedExecutorBuilder(settings, Names.GET, availableProcessors, 1000));
builders.put(Names.SEARCH, new FixedExecutorBuilder(settings, Names.SEARCH, searchThreadPoolSize(availableProcessors), 1000));
builders.put(Names.MANAGEMENT, new ScalingExecutorBuilder(Names.MANAGEMENT, 1, 5, TimeValue.timeValueMinutes(5)));
// no queue as this means clients will need to handle rejections on listener queue even if the operation succeeded
// the assumption here is that the listeners should be very lightweight on the listeners side
builders.put(Names.LISTENER, new FixedExecutorBuilder(settings, Names.LISTENER, halfProcMaxAt10, -1));
builders.put(Names.FLUSH, new ScalingExecutorBuilder(Names.FLUSH, 1, halfProcMaxAt5, TimeValue.timeValueMinutes(5)));
builders.put(Names.REFRESH, new ScalingExecutorBuilder(Names.REFRESH, 1, halfProcMaxAt10, TimeValue.timeValueMinutes(5)));
builders.put(Names.WARMER, new ScalingExecutorBuilder(Names.WARMER, 1, halfProcMaxAt5, TimeValue.timeValueMinutes(5)));
builders.put(Names.SNAPSHOT, new ScalingExecutorBuilder(Names.SNAPSHOT, 1, halfProcMaxAt5, TimeValue.timeValueMinutes(5)));
builders.put(Names.FETCH_SHARD_STARTED, new ScalingExecutorBuilder(Names.FETCH_SHARD_STARTED, 1, 2 * availableProcessors, TimeValue.timeValueMinutes(5)));
builders.put(Names.FORCE_MERGE, new FixedExecutorBuilder(settings, Names.FORCE_MERGE, 1, -1));
builders.put(Names.FETCH_SHARD_STORE, new ScalingExecutorBuilder(Names.FETCH_SHARD_STORE, 1, 2 * availableProcessors, TimeValue.timeValueMinutes(5)));
for (final ExecutorBuilder builder : customBuilders) {
if (builders.containsKey(builder.name())) {
throw new IllegalArgumentException("builder with name [" + builder.name() + "] already exists");
}
builders.put(builder.name(), builder);
}
this.builders = Collections.unmodifiableMap(builders);
threadContext = new ThreadContext(settings);
final Map executors = new HashMap<>();
for (@SuppressWarnings("unchecked") final Map.Entry entry : builders.entrySet()) {
final ExecutorBuilder.ExecutorSettings executorSettings = entry.getValue().getSettings(settings);
final ExecutorHolder executorHolder = entry.getValue().build(executorSettings, threadContext);
if (executors.containsKey(executorHolder.info.getName())) {
throw new IllegalStateException("duplicate executors with name [" + executorHolder.info.getName() + "] registered");
}
logger.debug("created thread pool: {}", entry.getValue().formatInfo(executorHolder.info));
executors.put(entry.getKey(), executorHolder);
}
executors.put(Names.SAME, new ExecutorHolder(DIRECT_EXECUTOR, new Info(Names.SAME, ThreadPoolType.DIRECT)));
this.executors = unmodifiableMap(executors);
this.scheduler = new ScheduledThreadPoolExecutor(1, EsExecutors.daemonThreadFactory(settings, "scheduler"), new EsAbortPolicy());
this.scheduler.setExecuteExistingDelayedTasksAfterShutdownPolicy(false);
this.scheduler.setContinueExistingPeriodicTasksAfterShutdownPolicy(false);
this.scheduler.setRemoveOnCancelPolicy(true);
TimeValue estimatedTimeInterval = ESTIMATED_TIME_INTERVAL_SETTING.get(settings);
this.cachedTimeThread = new CachedTimeThread(EsExecutors.threadName(settings, "[timer]"), estimatedTimeInterval.millis());
this.cachedTimeThread.start();
}
/**
* Returns a value of milliseconds that may be used for relative time calculations.
*
* This method should only be used for calculating time deltas. For an epoch based
* timestamp, see {@link #absoluteTimeInMillis()}.
*/
public long relativeTimeInMillis() {
return cachedTimeThread.relativeTimeInMillis();
}
/**
* Returns the value of milliseconds since UNIX epoch.
*
* This method should only be used for exact date/time formatting. For calculating
* time deltas that should not suffer from negative deltas, which are possible with
* this method, see {@link #relativeTimeInMillis()}.
*/
public long absoluteTimeInMillis() {
return cachedTimeThread.absoluteTimeInMillis();
}
public Counter estimatedTimeInMillisCounter() {
return cachedTimeThread.counter;
}
public ThreadPoolInfo info() {
List infos = new ArrayList<>();
for (ExecutorHolder holder : executors.values()) {
String name = holder.info.getName();
// no need to have info on "same" thread pool
if ("same".equals(name)) {
continue;
}
infos.add(holder.info);
}
return new ThreadPoolInfo(infos);
}
public Info info(String name) {
ExecutorHolder holder = executors.get(name);
if (holder == null) {
return null;
}
return holder.info;
}
public ThreadPoolStats stats() {
List stats = new ArrayList<>();
for (ExecutorHolder holder : executors.values()) {
String name = holder.info.getName();
// no need to have info on "same" thread pool
if ("same".equals(name)) {
continue;
}
int threads = -1;
int queue = -1;
int active = -1;
long rejected = -1;
int largest = -1;
long completed = -1;
if (holder.executor() instanceof ThreadPoolExecutor) {
ThreadPoolExecutor threadPoolExecutor = (ThreadPoolExecutor) holder.executor();
threads = threadPoolExecutor.getPoolSize();
queue = threadPoolExecutor.getQueue().size();
active = threadPoolExecutor.getActiveCount();
largest = threadPoolExecutor.getLargestPoolSize();
completed = threadPoolExecutor.getCompletedTaskCount();
RejectedExecutionHandler rejectedExecutionHandler = threadPoolExecutor.getRejectedExecutionHandler();
if (rejectedExecutionHandler instanceof XRejectedExecutionHandler) {
rejected = ((XRejectedExecutionHandler) rejectedExecutionHandler).rejected();
}
}
stats.add(new ThreadPoolStats.Stats(name, threads, queue, active, rejected, largest, completed));
}
return new ThreadPoolStats(stats);
}
/**
* Get the generic executor service. This executor service {@link Executor#execute(Runnable)} method will run the {@link Runnable} it
* is given in the {@link ThreadContext} of the thread that queues it.
*/
public ExecutorService generic() {
return executor(Names.GENERIC);
}
/**
* Get the executor service with the given name. This executor service's {@link Executor#execute(Runnable)} method will run the
* {@link Runnable} it is given in the {@link ThreadContext} of the thread that queues it.
*
* @param name the name of the executor service to obtain
* @throws IllegalArgumentException if no executor service with the specified name exists
*/
public ExecutorService executor(String name) {
final ExecutorHolder holder = executors.get(name);
if (holder == null) {
throw new IllegalArgumentException("no executor service found for [" + name + "]");
}
return holder.executor();
}
public ScheduledExecutorService scheduler() {
return this.scheduler;
}
/**
* Schedules a periodic action that runs on the specified thread pool.
*
* @param command the action to take
* @param interval the delay interval
* @param executor The name of the thread pool on which to execute this task. {@link Names#SAME} means "execute on the scheduler thread",
* which there is only one of. Executing blocking or long running code on the {@link Names#SAME} thread pool should never
* be done as it can cause issues with the cluster
* @return a {@link Cancellable} that can be used to cancel the subsequent runs of the command. If the command is running, it will
* not be interrupted.
*/
public Cancellable scheduleWithFixedDelay(Runnable command, TimeValue interval, String executor) {
return new ReschedulingRunnable(command, interval, executor, this);
}
/**
* Schedules a one-shot command to run after a given delay. The command is not run in the context of the calling thread. To preserve the
* context of the calling thread you may call threadPool.getThreadContext().preserveContext on the runnable before passing
* it to this method.
*
* @param delay delay before the task executes
* @param executor the name of the thread pool on which to execute this task. SAME means "execute on the scheduler thread" which changes the
* meaning of the ScheduledFuture returned by this method. In that case the ScheduledFuture will complete only when the command
* completes.
* @param command the command to run
* @return a ScheduledFuture who's get will return when the task is has been added to its target thread pool and throw an exception if
* the task is canceled before it was added to its target thread pool. Once the task has been added to its target thread pool
* the ScheduledFuture will cannot interact with it.
* @throws EsRejectedExecutionException if the task cannot be scheduled for execution
*/
public ScheduledFuture schedule(TimeValue delay, String executor, Runnable command) {
if (!Names.SAME.equals(executor)) {
command = new ThreadedRunnable(command, executor(executor));
}
return scheduler.schedule(new LoggingRunnable(command), delay.millis(), TimeUnit.MILLISECONDS);
}
public void shutdown() {
cachedTimeThread.running = false;
cachedTimeThread.interrupt();
scheduler.shutdown();
for (ExecutorHolder executor : executors.values()) {
if (executor.executor() instanceof ThreadPoolExecutor) {
((ThreadPoolExecutor) executor.executor()).shutdown();
}
}
}
public void shutdownNow() {
cachedTimeThread.running = false;
cachedTimeThread.interrupt();
scheduler.shutdownNow();
for (ExecutorHolder executor : executors.values()) {
if (executor.executor() instanceof ThreadPoolExecutor) {
((ThreadPoolExecutor) executor.executor()).shutdownNow();
}
}
}
public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException {
boolean result = scheduler.awaitTermination(timeout, unit);
for (ExecutorHolder executor : executors.values()) {
if (executor.executor() instanceof ThreadPoolExecutor) {
result &= ((ThreadPoolExecutor) executor.executor()).awaitTermination(timeout, unit);
}
}
cachedTimeThread.join(unit.toMillis(timeout));
return result;
}
/**
* Constrains a value between minimum and maximum values
* (inclusive).
*
* @param value the value to constrain
* @param min the minimum acceptable value
* @param max the maximum acceptable value
* @return min if value is less than min, max if value is greater
* than value, otherwise value
*/
static int boundedBy(int value, int min, int max) {
return Math.min(max, Math.max(min, value));
}
static int halfNumberOfProcessorsMaxFive(int numberOfProcessors) {
return boundedBy((numberOfProcessors + 1) / 2, 1, 5);
}
static int halfNumberOfProcessorsMaxTen(int numberOfProcessors) {
return boundedBy((numberOfProcessors + 1) / 2, 1, 10);
}
static int twiceNumberOfProcessors(int numberOfProcessors) {
return boundedBy(2 * numberOfProcessors, 2, Integer.MAX_VALUE);
}
public static int searchThreadPoolSize(int availableProcessors) {
return ((availableProcessors * 3) / 2) + 1;
}
class LoggingRunnable implements Runnable {
private final Runnable runnable;
LoggingRunnable(Runnable runnable) {
this.runnable = runnable;
}
@Override
public void run() {
try {
runnable.run();
} catch (Exception e) {
logger.warn((Supplier) () -> new ParameterizedMessage("failed to run {}", runnable.toString()), e);
throw e;
}
}
@Override
public int hashCode() {
return runnable.hashCode();
}
@Override
public boolean equals(Object obj) {
return runnable.equals(obj);
}
@Override
public String toString() {
return "[threaded] " + runnable.toString();
}
}
class ThreadedRunnable implements Runnable {
private final Runnable runnable;
private final Executor executor;
ThreadedRunnable(Runnable runnable, Executor executor) {
this.runnable = runnable;
this.executor = executor;
}
@Override
public void run() {
executor.execute(runnable);
}
@Override
public int hashCode() {
return runnable.hashCode();
}
@Override
public boolean equals(Object obj) {
return runnable.equals(obj);
}
@Override
public String toString() {
return "[threaded] " + runnable.toString();
}
}
/**
* A thread to cache millisecond time values from
* {@link System#nanoTime()} and {@link System#currentTimeMillis()}.
*
* The values are updated at a specified interval.
*/
static class CachedTimeThread extends Thread {
final long interval;
final TimeCounter counter;
volatile boolean running = true;
volatile long relativeMillis;
volatile long absoluteMillis;
CachedTimeThread(String name, long interval) {
super(name);
this.interval = interval;
this.relativeMillis = TimeValue.nsecToMSec(System.nanoTime());
this.absoluteMillis = System.currentTimeMillis();
this.counter = new TimeCounter();
setDaemon(true);
}
/**
* Return the current time used for relative calculations. This is
* {@link System#nanoTime()} truncated to milliseconds.
*/
long relativeTimeInMillis() {
return relativeMillis;
}
/**
* Return the current epoch time, used to find absolute time. This is
* a cached version of {@link System#currentTimeMillis()}.
*/
long absoluteTimeInMillis() {
return absoluteMillis;
}
@Override
public void run() {
while (running) {
relativeMillis = TimeValue.nsecToMSec(System.nanoTime());
absoluteMillis = System.currentTimeMillis();
try {
Thread.sleep(interval);
} catch (InterruptedException e) {
running = false;
return;
}
}
}
private class TimeCounter extends Counter {
@Override
public long addAndGet(long delta) {
throw new UnsupportedOperationException();
}
@Override
public long get() {
return relativeMillis;
}
}
}
static class ExecutorHolder {
private final ExecutorService executor;
public final Info info;
ExecutorHolder(ExecutorService executor, Info info) {
assert executor instanceof EsThreadPoolExecutor || executor == DIRECT_EXECUTOR;
this.executor = executor;
this.info = info;
}
ExecutorService executor() {
return executor;
}
}
public static class Info implements Writeable, ToXContent {
private final String name;
private final ThreadPoolType type;
private final int min;
private final int max;
private final TimeValue keepAlive;
private final SizeValue queueSize;
public Info(String name, ThreadPoolType type) {
this(name, type, -1);
}
public Info(String name, ThreadPoolType type, int size) {
this(name, type, size, size, null, null);
}
public Info(String name, ThreadPoolType type, int min, int max, @Nullable TimeValue keepAlive, @Nullable SizeValue queueSize) {
this.name = name;
this.type = type;
this.min = min;
this.max = max;
this.keepAlive = keepAlive;
this.queueSize = queueSize;
}
public Info(StreamInput in) throws IOException {
name = in.readString();
type = ThreadPoolType.fromType(in.readString());
min = in.readInt();
max = in.readInt();
keepAlive = in.readOptionalWriteable(TimeValue::new);
queueSize = in.readOptionalWriteable(SizeValue::new);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
out.writeString(name);
out.writeString(type.getType());
out.writeInt(min);
out.writeInt(max);
out.writeOptionalWriteable(keepAlive);
out.writeOptionalWriteable(queueSize);
}
public String getName() {
return this.name;
}
public ThreadPoolType getThreadPoolType() {
return this.type;
}
public int getMin() {
return this.min;
}
public int getMax() {
return this.max;
}
@Nullable
public TimeValue getKeepAlive() {
return this.keepAlive;
}
@Nullable
public SizeValue getQueueSize() {
return this.queueSize;
}
@Override
public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
builder.startObject(name);
builder.field(Fields.TYPE, type.getType());
if (min != -1) {
builder.field(Fields.MIN, min);
}
if (max != -1) {
builder.field(Fields.MAX, max);
}
if (keepAlive != null) {
builder.field(Fields.KEEP_ALIVE, keepAlive.toString());
}
if (queueSize == null) {
builder.field(Fields.QUEUE_SIZE, -1);
} else {
builder.field(Fields.QUEUE_SIZE, queueSize.singles());
}
builder.endObject();
return builder;
}
static final class Fields {
static final String TYPE = "type";
static final String MIN = "min";
static final String MAX = "max";
static final String KEEP_ALIVE = "keep_alive";
static final String QUEUE_SIZE = "queue_size";
}
}
/**
* Returns true if the given service was terminated successfully. If the termination timed out,
* the service is null this method will return false.
*/
public static boolean terminate(ExecutorService service, long timeout, TimeUnit timeUnit) {
if (service != null) {
service.shutdown();
if (awaitTermination(service, timeout, timeUnit)) return true;
service.shutdownNow();
return awaitTermination(service, timeout, timeUnit);
}
return false;
}
private static boolean awaitTermination(
final ExecutorService service,
final long timeout,
final TimeUnit timeUnit) {
try {
if (service.awaitTermination(timeout, timeUnit)) {
return true;
}
} catch (final InterruptedException e) {
Thread.currentThread().interrupt();
}
return false;
}
/**
* Returns true if the given pool was terminated successfully. If the termination timed out,
* the service is null this method will return false.
*/
public static boolean terminate(ThreadPool pool, long timeout, TimeUnit timeUnit) {
if (pool != null) {
try {
pool.shutdown();
if (awaitTermination(pool, timeout, timeUnit)) return true;
// last resort
pool.shutdownNow();
return awaitTermination(pool, timeout, timeUnit);
} finally {
IOUtils.closeWhileHandlingException(pool);
}
}
return false;
}
private static boolean awaitTermination(
final ThreadPool pool,
final long timeout,
final TimeUnit timeUnit) {
try {
if (pool.awaitTermination(timeout, timeUnit)) {
return true;
}
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
return false;
}
@Override
public void close() throws IOException {
threadContext.close();
}
public ThreadContext getThreadContext() {
return threadContext;
}
/**
* This interface represents an object whose execution may be cancelled during runtime.
*/
public interface Cancellable {
/**
* Cancel the execution of this object. This method is idempotent.
*/
void cancel();
/**
* Check if the execution has been cancelled
* @return true if cancelled
*/
boolean isCancelled();
}
/**
* This class encapsulates the scheduling of a {@link Runnable} that needs to be repeated on a interval. For example, checking a value
* for cleanup every second could be done by passing in a Runnable that can perform the check and the specified interval between
* executions of this runnable. NOTE: the runnable is only rescheduled to run again after completion of the runnable.
*
* For this class, completion means that the call to {@link Runnable#run()} returned or an exception was thrown and caught. In
* case of an exception, this class will log the exception and reschedule the runnable for its next execution. This differs from the
* {@link ScheduledThreadPoolExecutor#scheduleWithFixedDelay(Runnable, long, long, TimeUnit)} semantics as an exception there would
* terminate the rescheduling of the runnable.
*/
static final class ReschedulingRunnable extends AbstractRunnable implements Cancellable {
private final Runnable runnable;
private final TimeValue interval;
private final String executor;
private final ThreadPool threadPool;
private volatile boolean run = true;
/**
* Creates a new rescheduling runnable and schedules the first execution to occur after the interval specified
*
* @param runnable the {@link Runnable} that should be executed periodically
* @param interval the time interval between executions
* @param executor the executor where this runnable should be scheduled to run
* @param threadPool the {@link ThreadPool} instance to use for scheduling
*/
ReschedulingRunnable(Runnable runnable, TimeValue interval, String executor, ThreadPool threadPool) {
this.runnable = runnable;
this.interval = interval;
this.executor = executor;
this.threadPool = threadPool;
threadPool.schedule(interval, executor, this);
}
@Override
public void cancel() {
run = false;
}
@Override
public boolean isCancelled() {
return run == false;
}
@Override
public void doRun() {
// always check run here since this may have been cancelled since the last execution and we do not want to run
if (run) {
runnable.run();
}
}
@Override
public void onFailure(Exception e) {
threadPool.logger.warn((Supplier) () -> new ParameterizedMessage("failed to run scheduled task [{}] on thread pool [{}]", runnable.toString(), executor), e);
}
@Override
public void onRejection(Exception e) {
run = false;
if (threadPool.logger.isDebugEnabled()) {
threadPool.logger.debug((Supplier) () -> new ParameterizedMessage("scheduled task [{}] was rejected on thread pool [{}]", runnable, executor), e);
}
}
@Override
public void onAfter() {
// if this has not been cancelled reschedule it to run again
if (run) {
try {
threadPool.schedule(interval, executor, this);
} catch (final EsRejectedExecutionException e) {
onRejection(e);
}
}
}
}
public static boolean assertNotScheduleThread(String reason) {
assert Thread.currentThread().getName().contains("scheduler") == false :
"Expected current thread [" + Thread.currentThread() + "] to not be the scheduler thread. Reason: [" + reason + "]";
return true;
}
}