| 1 | /** |
| 2 | * Licensed to jclouds, Inc. (jclouds) under one or more |
| 3 | * contributor license agreements. See the NOTICE file |
| 4 | * distributed with this work for additional information |
| 5 | * regarding copyright ownership. jclouds licenses this file |
| 6 | * to you under the Apache License, Version 2.0 (the |
| 7 | * "License"); you may not use this file except in compliance |
| 8 | * with the License. You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, |
| 13 | * software distributed under the License is distributed on an |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| 15 | * KIND, either express or implied. See the License for the |
| 16 | * specific language governing permissions and limitations |
| 17 | * under the License. |
| 18 | */ |
| 19 | package org.jclouds.concurrent.config; |
| 20 | |
| 21 | import static com.google.common.base.Preconditions.checkNotNull; |
| 22 | import static org.jclouds.concurrent.DynamicExecutors.newScalingThreadPool; |
| 23 | |
| 24 | import java.io.Closeable; |
| 25 | import java.io.IOException; |
| 26 | import java.util.Collection; |
| 27 | import java.util.List; |
| 28 | import java.util.concurrent.Callable; |
| 29 | import java.util.concurrent.ExecutionException; |
| 30 | import java.util.concurrent.ExecutorService; |
| 31 | import java.util.concurrent.Executors; |
| 32 | import java.util.concurrent.Future; |
| 33 | import java.util.concurrent.TimeUnit; |
| 34 | import java.util.concurrent.TimeoutException; |
| 35 | |
| 36 | import javax.annotation.Resource; |
| 37 | import javax.inject.Inject; |
| 38 | import javax.inject.Named; |
| 39 | import javax.inject.Singleton; |
| 40 | |
| 41 | import org.jclouds.Constants; |
| 42 | import org.jclouds.concurrent.MoreExecutors; |
| 43 | import org.jclouds.concurrent.SingleThreaded; |
| 44 | import org.jclouds.lifecycle.Closer; |
| 45 | import org.jclouds.logging.Logger; |
| 46 | |
| 47 | import com.google.common.annotations.VisibleForTesting; |
| 48 | import com.google.common.util.concurrent.ThreadFactoryBuilder; |
| 49 | import com.google.inject.AbstractModule; |
| 50 | import com.google.inject.Provides; |
| 51 | |
| 52 | /** |
| 53 | * Configures {@link ExecutorService}. |
| 54 | * |
| 55 | * Note that this uses threads. |
| 56 | * |
| 57 | * <p> |
| 58 | * This extends the underlying Future to expose a description (the task's toString) and the submission context (stack trace). |
| 59 | * The submission stack trace is appended to relevant stack traces on exceptions that are returned, |
| 60 | * so the user can see the logical chain of execution (in the executor, and where it was passed to the executor). |
| 61 | * |
| 62 | * @author Adrian Cole |
| 63 | */ |
| 64 | @ConfiguresExecutorService |
| 65 | public class ExecutorServiceModule extends AbstractModule { |
| 66 | |
| 67 | @VisibleForTesting |
| 68 | static final class ShutdownExecutorOnClose implements Closeable { |
| 69 | @Resource |
| 70 | protected Logger logger = Logger.NULL; |
| 71 | |
| 72 | private final ExecutorService service; |
| 73 | |
| 74 | private ShutdownExecutorOnClose(ExecutorService service) { |
| 75 | this.service = service; |
| 76 | } |
| 77 | |
| 78 | @Override |
| 79 | public void close() throws IOException { |
| 80 | List<Runnable> runnables = service.shutdownNow(); |
| 81 | if (runnables.size() > 0) |
| 82 | logger.warn("when shutting down executor %s, runnables outstanding: %s", service, runnables); |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | @VisibleForTesting |
| 87 | final ExecutorService userExecutorFromConstructor; |
| 88 | @VisibleForTesting |
| 89 | final ExecutorService ioExecutorFromConstructor; |
| 90 | |
| 91 | @Inject |
| 92 | public ExecutorServiceModule(@Named(Constants.PROPERTY_USER_THREADS) ExecutorService userThreads, |
| 93 | @Named(Constants.PROPERTY_IO_WORKER_THREADS) ExecutorService ioThreads) { |
| 94 | this.userExecutorFromConstructor = addToStringOnSubmit(checkNotGuavaSameThreadExecutor(userThreads)); |
| 95 | this.ioExecutorFromConstructor = addToStringOnSubmit(checkNotGuavaSameThreadExecutor(ioThreads)); |
| 96 | } |
| 97 | |
| 98 | static ExecutorService addToStringOnSubmit(ExecutorService executor) { |
| 99 | if (executor != null) { |
| 100 | return new DescribingExecutorService(executor); |
| 101 | } |
| 102 | return executor; |
| 103 | } |
| 104 | |
| 105 | static ExecutorService checkNotGuavaSameThreadExecutor(ExecutorService executor) { |
| 106 | // we detect behavior based on the class |
| 107 | if (executor != null && !(executor.getClass().isAnnotationPresent(SingleThreaded.class)) |
| 108 | && executor.getClass().getSimpleName().indexOf("SameThread") != -1) { |
| 109 | Logger.CONSOLE.warn( |
| 110 | "please switch from %s to %s or annotate your same threaded executor with @SingleThreaded", executor |
| 111 | .getClass().getName(), MoreExecutors.SameThreadExecutorService.class.getName()); |
| 112 | return MoreExecutors.sameThreadExecutor(); |
| 113 | } |
| 114 | return executor; |
| 115 | } |
| 116 | |
| 117 | public ExecutorServiceModule() { |
| 118 | this(null, null); |
| 119 | } |
| 120 | |
| 121 | @Override |
| 122 | protected void configure() { |
| 123 | } |
| 124 | |
| 125 | static class DescribingExecutorService implements ExecutorService { |
| 126 | |
| 127 | private final ExecutorService delegate; |
| 128 | |
| 129 | public DescribingExecutorService(ExecutorService delegate) { |
| 130 | this.delegate = checkNotNull(delegate, "delegate"); |
| 131 | } |
| 132 | |
| 133 | @Override |
| 134 | public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException { |
| 135 | return delegate.awaitTermination(timeout, unit); |
| 136 | } |
| 137 | |
| 138 | @Override |
| 139 | public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks) throws InterruptedException { |
| 140 | return delegate.invokeAll(tasks); |
| 141 | } |
| 142 | |
| 143 | @Override |
| 144 | public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) |
| 145 | throws InterruptedException { |
| 146 | return delegate.invokeAll(tasks, timeout, unit); |
| 147 | } |
| 148 | |
| 149 | @Override |
| 150 | public <T> T invokeAny(Collection<? extends Callable<T>> tasks) throws InterruptedException, ExecutionException { |
| 151 | return delegate.invokeAny(tasks); |
| 152 | } |
| 153 | |
| 154 | @Override |
| 155 | public <T> T invokeAny(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) |
| 156 | throws InterruptedException, ExecutionException, TimeoutException { |
| 157 | return delegate.invokeAny(tasks, timeout, unit); |
| 158 | } |
| 159 | |
| 160 | @Override |
| 161 | public boolean isShutdown() { |
| 162 | return delegate.isShutdown(); |
| 163 | } |
| 164 | |
| 165 | @Override |
| 166 | public boolean isTerminated() { |
| 167 | return delegate.isTerminated(); |
| 168 | } |
| 169 | |
| 170 | @Override |
| 171 | public void shutdown() { |
| 172 | delegate.shutdown(); |
| 173 | } |
| 174 | |
| 175 | @Override |
| 176 | public List<Runnable> shutdownNow() { |
| 177 | return delegate.shutdownNow(); |
| 178 | } |
| 179 | |
| 180 | @Override |
| 181 | public <T> Future<T> submit(Callable<T> task) { |
| 182 | return new DescribedFuture<T>(delegate.submit(task), task.toString(), getStackTraceHere()); |
| 183 | } |
| 184 | |
| 185 | @SuppressWarnings({ "unchecked", "rawtypes" }) |
| 186 | @Override |
| 187 | public Future<?> submit(Runnable task) { |
| 188 | return new DescribedFuture(delegate.submit(task), task.toString(), getStackTraceHere()); |
| 189 | } |
| 190 | |
| 191 | @Override |
| 192 | public <T> Future<T> submit(Runnable task, T result) { |
| 193 | return new DescribedFuture<T>(delegate.submit(task, result), task.toString(), getStackTraceHere()); |
| 194 | } |
| 195 | |
| 196 | @Override |
| 197 | public void execute(Runnable arg0) { |
| 198 | delegate.execute(arg0); |
| 199 | } |
| 200 | |
| 201 | @Override |
| 202 | public boolean equals(Object obj) { |
| 203 | return delegate.equals(obj); |
| 204 | } |
| 205 | |
| 206 | @Override |
| 207 | public int hashCode() { |
| 208 | return delegate.hashCode(); |
| 209 | } |
| 210 | |
| 211 | @Override |
| 212 | public String toString() { |
| 213 | return delegate.toString(); |
| 214 | } |
| 215 | |
| 216 | } |
| 217 | |
| 218 | static class DescribedFuture<T> implements Future<T> { |
| 219 | private final Future<T> delegate; |
| 220 | private final String description; |
| 221 | private StackTraceElement[] submissionTrace; |
| 222 | |
| 223 | public DescribedFuture(Future<T> delegate, String description, StackTraceElement[] submissionTrace) { |
| 224 | this.delegate = delegate; |
| 225 | this.description = description; |
| 226 | this.submissionTrace = submissionTrace; |
| 227 | } |
| 228 | |
| 229 | @Override |
| 230 | public boolean cancel(boolean arg0) { |
| 231 | return delegate.cancel(arg0); |
| 232 | } |
| 233 | |
| 234 | @Override |
| 235 | public T get() throws InterruptedException, ExecutionException { |
| 236 | try { |
| 237 | return delegate.get(); |
| 238 | } catch (ExecutionException e) { |
| 239 | throw ensureCauseHasSubmissionTrace(e); |
| 240 | } catch (InterruptedException e) { |
| 241 | throw ensureCauseHasSubmissionTrace(e); |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | @Override |
| 246 | public T get(long arg0, TimeUnit arg1) throws InterruptedException, ExecutionException, TimeoutException { |
| 247 | try { |
| 248 | return delegate.get(arg0, arg1); |
| 249 | } catch (ExecutionException e) { |
| 250 | throw ensureCauseHasSubmissionTrace(e); |
| 251 | } catch (InterruptedException e) { |
| 252 | throw ensureCauseHasSubmissionTrace(e); |
| 253 | } catch (TimeoutException e) { |
| 254 | throw ensureCauseHasSubmissionTrace(e); |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | /** This method does the work to ensure _if_ a submission stack trace was provided, |
| 259 | * it is included in the exception. most errors are thrown from the frame of the |
| 260 | * Future.get call, with a cause that took place in the executor's thread. |
| 261 | * We extend the stack trace of that cause with the submission stack trace. |
| 262 | * (An alternative would be to put the stack trace as a root cause, |
| 263 | * at the bottom of the stack, or appended to all traces, or inserted |
| 264 | * after the second cause, etc ... but since we can't change the "Caused by:" |
| 265 | * method in Throwable the compromise made here seems best.) |
| 266 | */ |
| 267 | private <ET extends Exception> ET ensureCauseHasSubmissionTrace(ET e) { |
| 268 | if (submissionTrace==null) return e; |
| 269 | if (e.getCause()==null) { |
| 270 | ExecutionException ee = new ExecutionException("task submitted from the following trace", null); |
| 271 | e.initCause(ee); |
| 272 | return e; |
| 273 | } |
| 274 | Throwable cause = e.getCause(); |
| 275 | StackTraceElement[] causeTrace = cause.getStackTrace(); |
| 276 | boolean causeIncludesSubmissionTrace = submissionTrace.length >= causeTrace.length; |
| 277 | for (int i=0; causeIncludesSubmissionTrace && i<submissionTrace.length; i++) { |
| 278 | if (!causeTrace[causeTrace.length-1-i].equals(submissionTrace[submissionTrace.length-1-i])) { |
| 279 | causeIncludesSubmissionTrace = false; |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | if (!causeIncludesSubmissionTrace) { |
| 284 | cause.setStackTrace(merge(causeTrace, submissionTrace)); |
| 285 | } |
| 286 | |
| 287 | return e; |
| 288 | } |
| 289 | |
| 290 | private StackTraceElement[] merge(StackTraceElement[] t1, StackTraceElement[] t2) { |
| 291 | StackTraceElement[] t12 = new StackTraceElement[t1.length + t2.length]; |
| 292 | System.arraycopy(t1, 0, t12, 0, t1.length); |
| 293 | System.arraycopy(t2, 0, t12, t1.length, t2.length); |
| 294 | return t12; |
| 295 | } |
| 296 | |
| 297 | @Override |
| 298 | public boolean isCancelled() { |
| 299 | return delegate.isCancelled(); |
| 300 | } |
| 301 | |
| 302 | @Override |
| 303 | public boolean isDone() { |
| 304 | return delegate.isDone(); |
| 305 | } |
| 306 | |
| 307 | @Override |
| 308 | public boolean equals(Object obj) { |
| 309 | return delegate.equals(obj); |
| 310 | } |
| 311 | |
| 312 | @Override |
| 313 | public int hashCode() { |
| 314 | return delegate.hashCode(); |
| 315 | } |
| 316 | |
| 317 | @Override |
| 318 | public String toString() { |
| 319 | return description; |
| 320 | } |
| 321 | |
| 322 | } |
| 323 | |
| 324 | @Provides |
| 325 | @Singleton |
| 326 | @Named(Constants.PROPERTY_USER_THREADS) |
| 327 | ExecutorService provideExecutorService(@Named(Constants.PROPERTY_USER_THREADS) int count, Closer closer) { |
| 328 | if (userExecutorFromConstructor != null) |
| 329 | return userExecutorFromConstructor; |
| 330 | return shutdownOnClose(addToStringOnSubmit(newThreadPoolNamed("user thread %d", count)), closer); |
| 331 | } |
| 332 | |
| 333 | @Provides |
| 334 | @Singleton |
| 335 | @Named(Constants.PROPERTY_IO_WORKER_THREADS) |
| 336 | ExecutorService provideIOExecutor(@Named(Constants.PROPERTY_IO_WORKER_THREADS) int count, Closer closer) { |
| 337 | if (ioExecutorFromConstructor != null) |
| 338 | return ioExecutorFromConstructor; |
| 339 | return shutdownOnClose(addToStringOnSubmit(newThreadPoolNamed("i/o thread %d", count)), closer); |
| 340 | } |
| 341 | |
| 342 | @VisibleForTesting |
| 343 | static ExecutorService shutdownOnClose(final ExecutorService service, Closer closer) { |
| 344 | closer.addToClose(new ShutdownExecutorOnClose(service)); |
| 345 | return service; |
| 346 | } |
| 347 | |
| 348 | @VisibleForTesting |
| 349 | static ExecutorService newCachedThreadPoolNamed(String name) { |
| 350 | return Executors.newCachedThreadPool(new ThreadFactoryBuilder().setNameFormat(name).setThreadFactory( |
| 351 | Executors.defaultThreadFactory()).build()); |
| 352 | } |
| 353 | |
| 354 | @VisibleForTesting |
| 355 | static ExecutorService newThreadPoolNamed(String name, int maxCount) { |
| 356 | return maxCount == 0 ? newCachedThreadPoolNamed(name) : newScalingThreadPoolNamed(name, maxCount); |
| 357 | } |
| 358 | |
| 359 | @VisibleForTesting |
| 360 | static ExecutorService newScalingThreadPoolNamed(String name, int maxCount) { |
| 361 | return newScalingThreadPool(1, maxCount, 60L * 1000, new ThreadFactoryBuilder().setNameFormat(name) |
| 362 | .setThreadFactory(Executors.defaultThreadFactory()).build()); |
| 363 | } |
| 364 | |
| 365 | /** returns the stack trace at the caller */ |
| 366 | static StackTraceElement[] getStackTraceHere() { |
| 367 | // remove the first two items in the stack trace (because the first one refers to the call to |
| 368 | // Thread.getStackTrace, and the second one is us) |
| 369 | StackTraceElement[] fullSubmissionTrace = Thread.currentThread().getStackTrace(); |
| 370 | StackTraceElement[] cleanedSubmissionTrace = new StackTraceElement[fullSubmissionTrace.length-2]; |
| 371 | System.arraycopy(fullSubmissionTrace, 2, cleanedSubmissionTrace, 0, cleanedSubmissionTrace.length); |
| 372 | return cleanedSubmissionTrace; |
| 373 | } |
| 374 | |
| 375 | } |