opendev/gerrit
Code Issues Proposed changes

Fix copying of LoggingContext to background threads

Browse Source 
We used a custom ThreadFactory to copy the LoggingContext to newly
created threads, but this is not sufficient since the new thread may be
cached in a thread pool and then be reused to execute further tasks. We
must copy the LoggingContext each time a task is executed in a
background thread, not only when the background thread is created.

To copy the LoggingContext when a Runnable or Callable is executed in
the background we implement LoggingContext aware wrappers for them.

We use 2 ways for executing tasks in background threads:

1. ExecutorService/ScheduledExecutorService
2. WorkQueue.Executor (custom executor)

To ensure the copying of the LoggingContext when a task is executed in
the background we now do:

1. Wrap each ExecutorService/ScheduledExecutorService with a wrapper
   that wraps each Runnable/Callable that is passed in with a
   LoggingContext aware wrapper.

2. Wrap each Runnable/Callable that is passed into WorkQueue.Executor
   with a LoggingContext aware wrapper.

For WorkQueue.Executor we would ideally wrap the Runnable/Callable in
decorateTask but the Runnable/Callable that is being executed is
contained in a RunnableScheduledFuture and we cannot access it
(decorateTask in ScheduledThreadPoolExecutor from which we inherit
ignores the passed in Runnable and only the passed in
RunnableScheduledFuture is relevant). Also overriding the
newTaskFor(Runnable)/newTaskFor(Callable) methods does not work since
ScheduledThreadPoolExecutor is creating tasks directly without invoking
any newTaskFor method.

Change-Id: I106dcdf6478c58dfa6fe1d7952a87aa16ead1a93
Signed-off-by: Edwin Kempin <ekempin@google.com>
This commit is contained in:
Edwin Kempin
2018-08-31 21:54:13 +02:00
parent 7f0127a3bd
commit f59c09b924
19 changed files with 629 additions and 268 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
java/com/google/gerrit/server/config/SysExecutorModule.java
View File

@@ -19,7 +19,7 @@ import com.google.common.util.concurrent.MoreExecutors;
import com.google.common.util.concurrent.ThreadFactoryBuilder;
import com.google.gerrit.server.FanOutExecutor;
import com.google.gerrit.server.git.WorkQueue;
import com.google.gerrit.server.logging.LoggingContextAwareThreadFactory;
import com.google.gerrit.server.logging.LoggingContextAwareExecutorService;
import com.google.inject.AbstractModule;
import com.google.inject.Provides;
import com.google.inject.Singleton;
@@ -83,18 +83,18 @@ public class SysExecutorModule extends AbstractModule {
return MoreExecutors.newDirectExecutorService();
}
return MoreExecutors.listeningDecorator(
MoreExecutors.getExitingExecutorService(
new ThreadPoolExecutor(
1,
poolSize,
10,
TimeUnit.MINUTES,
new ArrayBlockingQueue<Runnable>(poolSize),
new ThreadFactoryBuilder()
.setThreadFactory(new LoggingContextAwareThreadFactory())
.setNameFormat("ChangeUpdate-%d")
.setDaemon(true)
.build(),
new ThreadPoolExecutor.CallerRunsPolicy())));
new LoggingContextAwareExecutorService(
MoreExecutors.getExitingExecutorService(
new ThreadPoolExecutor(
1,
poolSize,
10,
TimeUnit.MINUTES,
new ArrayBlockingQueue<Runnable>(poolSize),
new ThreadFactoryBuilder()
.setNameFormat("ChangeUpdate-%d")
.setDaemon(true)
.build(),
new ThreadPoolExecutor.CallerRunsPolicy()))));
}
}