org.apache.thrift.server

Class TThreadedSelectorServerWithFix

java.lang.Object

org.apache.thrift.server.TServer

org.apache.thrift.server.AbstractNonblockingServer

org.apache.thrift.server.TThreadedSelectorServerWithFix

public class TThreadedSelectorServerWithFix
extends org.apache.thrift.server.AbstractNonblockingServer

A Half-Sync/Half-Async server with a separate pool of threads to handle non-blocking I/O. Accepts are handled on a single thread, and a configurable number of nonblocking selector threads manage reading and writing of client connections. A synchronous worker thread pool handles processing of requests. Performs better than TNonblockingServer/THsHaServer in multi-core environments when the the bottleneck is CPU on the single selector thread handling I/O. In addition, because the accept handling is decoupled from reads/writes and invocation, the server has better ability to handle back- pressure from new connections (e.g. stop accepting when busy). Like TNonblockingServer, it relies on the use of TFramedTransport.

This implementation fixes the issue where TThreadedSelectorServer (v0.9.0) would hang during stop, which can happen when Thrift server is stopped when AcceptThread is blocked on adding a connection to acceptedQueue. The fix is to block accept thread for a set time when adding new connections to accepted queue, this way the accept thread can check for stop flag every now and then.

See Also:

TEPHRA-132

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	TThreadedSelectorServerWithFix.AcceptThread The thread that selects on the server transport (listen socket) and accepts new connections to hand off to the IO selector threads
static class	TThreadedSelectorServerWithFix.Args
protected class	TThreadedSelectorServerWithFix.SelectorThread The SelectorThread(s) will be doing all the selecting on accepted active connections.
protected class	TThreadedSelectorServerWithFix.SelectorThreadLoadBalancer A round robin load balancer for choosing selector threads for new connections.

Nested classes/interfaces inherited from class org.apache.thrift.server.AbstractNonblockingServer

org.apache.thrift.server.AbstractNonblockingServer.AbstractNonblockingServerArgs<T extends org.apache.thrift.server.AbstractNonblockingServer.AbstractNonblockingServerArgs<T>>, org.apache.thrift.server.AbstractNonblockingServer.AbstractSelectThread, org.apache.thrift.server.AbstractNonblockingServer.FrameBuffer

Nested classes/interfaces inherited from class org.apache.thrift.server.TServer

org.apache.thrift.server.TServer.AbstractServerArgs<T extends org.apache.thrift.server.TServer.AbstractServerArgs<T>>

Field Summary

Fields inherited from class org.apache.thrift.server.TServer

eventHandler_, inputProtocolFactory_, inputTransportFactory_, outputProtocolFactory_, outputTransportFactory_, processorFactory_, serverTransport_

Constructor Summary

Constructors

Constructor and Description
TThreadedSelectorServerWithFix(TThreadedSelectorServerWithFix.Args args) Create the server with the specified Args configuration

Method Summary

Modifier and Type	Method and Description
protected static ExecutorService	createDefaultExecutor(TThreadedSelectorServerWithFix.Args options) Helper to create the invoker if one is not specified
protected TThreadedSelectorServerWithFix.SelectorThreadLoadBalancer	createSelectorThreadLoadBalancer(Collection<? extends TThreadedSelectorServerWithFix.SelectorThread> threads) Creates a SelectorThreadLoadBalancer to be used by the accept thread for assigning newly accepted connections across the threads.
protected Runnable	getRunnable(org.apache.thrift.server.AbstractNonblockingServer.FrameBuffer frameBuffer)
protected void	gracefullyShutdownInvokerPool()
protected void	joinThreads()
protected boolean	requestInvoke(org.apache.thrift.server.AbstractNonblockingServer.FrameBuffer frameBuffer) We override the standard invoke method here to queue the invocation for invoker service instead of immediately invoking.
protected boolean	startThreads() Start the accept and selector threads running to deal with clients.
void	stop() Stop serving and shut everything down.
protected void	waitForShutdown() Joins the accept and selector threads and shuts down the executor service.

Methods inherited from class org.apache.thrift.server.AbstractNonblockingServer

getEventHandler, serve, setServerEventHandler, startListening, stopListening

Methods inherited from class org.apache.thrift.server.TServer

isServing, setServing

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TThreadedSelectorServerWithFix

public TThreadedSelectorServerWithFix(TThreadedSelectorServerWithFix.Args args)

Create the server with the specified Args configuration

Method Detail

startThreads

protected boolean startThreads()

Start the accept and selector threads running to deal with clients.

Specified by:

startThreads in class org.apache.thrift.server.AbstractNonblockingServer

Returns:

true if everything went ok, false if we couldn't start for some reason.

waitForShutdown

protected void waitForShutdown()

Joins the accept and selector threads and shuts down the executor service.

Specified by:

waitForShutdown in class org.apache.thrift.server.AbstractNonblockingServer

joinThreads

protected void joinThreads()
                    throws InterruptedException

Throws:

InterruptedException

stop

public void stop()

Stop serving and shut everything down.

Overrides:

stop in class org.apache.thrift.server.TServer

gracefullyShutdownInvokerPool

protected void gracefullyShutdownInvokerPool()

requestInvoke

protected boolean requestInvoke(org.apache.thrift.server.AbstractNonblockingServer.FrameBuffer frameBuffer)

We override the standard invoke method here to queue the invocation for invoker service instead of immediately invoking. If there is no thread pool, handle the invocation inline on this thread

Specified by:

requestInvoke in class org.apache.thrift.server.AbstractNonblockingServer

getRunnable

protected Runnable getRunnable(org.apache.thrift.server.AbstractNonblockingServer.FrameBuffer frameBuffer)

createDefaultExecutor

protected static ExecutorService createDefaultExecutor(TThreadedSelectorServerWithFix.Args options)

Helper to create the invoker if one is not specified

createSelectorThreadLoadBalancer

protected TThreadedSelectorServerWithFix.SelectorThreadLoadBalancer createSelectorThreadLoadBalancer(Collection<? extends TThreadedSelectorServerWithFix.SelectorThread> threads)

Creates a SelectorThreadLoadBalancer to be used by the accept thread for assigning newly accepted connections across the threads.