dbbc6ad73f
When a Netty application shuts down, a user often sees a REE (RejectedExecutionException). A REE is raised due to various reasons we don't have control over, such as: - A client connects to a server while the server is shutting down. - An event is triggered for a closed Channel while its event loop is also shutting down. Some of them are: - channelDeregistered (triggered after a channel is closed) - freeIn/OutboundBuffer (triggered after channelDeregistered) - userEventTriggered (triggered anytime) To address this issue, a new method called confirmShutdown() has been added to SingleThreadEventExecutor. After a user calls shutdown(), confirmShutdown() runs any remaining tasks in the task queue and ensures no events are triggered for last 2 seconds. If any task are added to the task queue before 2 seconds passes, confirmShutdown() prevents the event loop from terminating by returning false. Now that SingleThreadEventExecutor needs to accept tasks even after shutdown(), its execute() method only rejects the task after the event loop is terminated (i.e. isTerminated() returns true.) Except that, there's no change in semantics. SingleThreadEventExecutor also checks if its subclass called confirmShutdown() in its run() implementation, so that Netty developers can make sure they shut down their event loop impementation correctly. It also fixes a bug in AioSocketChannel, revealed by delayed shutdown, where an inboundBufferUpdated() event is triggered on a closed Channel with deallocated buffers. Caveats: Because SingleThreadEventExecutor.takeTask() does not have a notion of timeout, confirmShutdown() adds a dummy task (WAKEUP_TASK) to wake up takeTask() immediately and instead sleeps hard-coded 100ms. I'll address this issue later by modifying takeTask() times out dynamically. Miscellaneous changes: SingleThreadEventExecutor.wakeup() now has the default implementation. Instead of interrupting the current thread, it simply adds a dummy task (WAKEUP_TASK) to the task queue, which is more elegant and efficient. NioEventLoop is the only implementation that overrides it. All other implementations' wakeup()s were removed thanks to this change. |
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| all | ||
| buffer | ||
| codec | ||
| codec-http | ||
| codec-socks | ||
| common | ||
| example | ||
| handler | ||
| license | ||
| metrics-yammer | ||
| tarball | ||
| testsuite | ||
| transport | ||
| .fbfilter.xml | ||
| .fbprefs | ||
| .gitignore | ||
| LICENSE.txt | ||
| NOTICE.txt | ||
| pom.xml | ||
| README.md | ||
The Netty Project
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients.
Links
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Web Site: http://netty.io/
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Docs: http://netty.io/docs/
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Blog: http://netty.io/blog/
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Twitter: @netty_project
Getting Netty
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Download Page: http://netty.io/downloads/
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Maven Repository:
<dependencies>
...
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty</artifactId>
<version>X.Y.Z.Q</version>
<scope>compile</scope>
</dependency>
...
</dependencies>
Developer Information
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Netty is setup to build using Maven
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You need JDK 7 to build Netty. Netty will run with JDK 5 (3.x) and JDK 6 (4).
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master branch contains code for Netty 4.x
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3 branch contains code for Netty 3.x