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本文主要研究一下rocketmq的NettyClientConfig
NettyClientConfig
org/apache/rocketmq/remoting/netty/NettyClientConfig.java
public class NettyClientConfig {
/**
* Worker thread number
*/
private int clientWorkerThreads = 4;
private int clientCallbackExecutorThreads = Runtime.getRuntime().availableProcessors();
private int clientOnewaySemaphoreValue = NettySystemConfig.CLIENT_ONEWAY_SEMAPHORE_VALUE;
private int clientAsyncSemaphoreValue = NettySystemConfig.CLIENT_ASYNC_SEMAPHORE_VALUE;
private int connectTimeoutMillis = 3000;
private long channelNotActiveInterval = 1000 * 60;
/**
* IdleStateEvent will be triggered when neither read nor write was performed for
* the specified period of this time. Specify {@code 0} to disable
*/
private int clientChannelMaxIdleTimeSeconds = 120;
private int clientSocketSndBufSize = NettySystemConfig.socketSndbufSize;
private int clientSocketRcvBufSize = NettySystemConfig.socketRcvbufSize;
private boolean clientPooledByteBufAllocatorEnable = false;
private boolean clientCloseSocketIfTimeout = false;
private boolean useTLS;
//......
}這裏主要有幾個參數：
- clientWorkerThreads，默認爲4
- clientCallbackExecutorThreads，默認爲cpu核數
- clientOnewaySemaphoreValue，默認爲NettySystemConfig.CLIENT_ONEWAY_SEMAPHORE_VALUE，如果沒有指定，則默認爲65535
- clientAsyncSemaphoreValue，默認爲NettySystemConfig.CLIENT_ASYNC_SEMAPHORE_VALUE，如果沒有指定，則默認爲65535
- connectTimeoutMillis，默認爲3秒
- channelNotActiveInterval，默認爲60秒
- clientChannelMaxIdleTimeSeconds，默認爲爲120秒
- clientSocketSndBufSize，取NettySystemConfig.socketSndbufSize，如果沒有指定，默認爲65535
- clientSocketRcvBufSize，取NettySystemConfig.socketRcvbufSize，如果沒有指定，默認爲65535
- clientPooledByteBufAllocatorEnable，默認爲false
- clientCloseSocketIfTimeout，默認爲false
- useTLS，默認爲false
NettySystemConfig
org/apache/rocketmq/remoting/netty/NettySystemConfig.java
public class NettySystemConfig {
public static final String COM_ROCKETMQ_REMOTING_NETTY_POOLED_BYTE_BUF_ALLOCATOR_ENABLE =
"com.rocketmq.remoting.nettyPooledByteBufAllocatorEnable";
public static final String COM_ROCKETMQ_REMOTING_SOCKET_SNDBUF_SIZE =
"com.rocketmq.remoting.socket.sndbuf.size";
public static final String COM_ROCKETMQ_REMOTING_SOCKET_RCVBUF_SIZE =
"com.rocketmq.remoting.socket.rcvbuf.size";
public static final String COM_ROCKETMQ_REMOTING_CLIENT_ASYNC_SEMAPHORE_VALUE =
"com.rocketmq.remoting.clientAsyncSemaphoreValue";
public static final String COM_ROCKETMQ_REMOTING_CLIENT_ONEWAY_SEMAPHORE_VALUE =
"com.rocketmq.remoting.clientOnewaySemaphoreValue";
public static final boolean NETTY_POOLED_BYTE_BUF_ALLOCATOR_ENABLE = //
Boolean.parseBoolean(System.getProperty(COM_ROCKETMQ_REMOTING_NETTY_POOLED_BYTE_BUF_ALLOCATOR_ENABLE, "false"));
public static final int CLIENT_ASYNC_SEMAPHORE_VALUE = //
Integer.parseInt(System.getProperty(COM_ROCKETMQ_REMOTING_CLIENT_ASYNC_SEMAPHORE_VALUE, "65535"));
public static final int CLIENT_ONEWAY_SEMAPHORE_VALUE =
Integer.parseInt(System.getProperty(COM_ROCKETMQ_REMOTING_CLIENT_ONEWAY_SEMAPHORE_VALUE, "65535"));
public static int socketSndbufSize =
Integer.parseInt(System.getProperty(COM_ROCKETMQ_REMOTING_SOCKET_SNDBUF_SIZE, "65535"));
public static int socketRcvbufSize =
Integer.parseInt(System.getProperty(COM_ROCKETMQ_REMOTING_SOCKET_RCVBUF_SIZE, "65535"));
}- 採取先從系統變量讀取，沒有則返回默認值
NettyRemotingClient
org/apache/rocketmq/remoting/netty/NettyRemotingClient.java
public class NettyRemotingClient extends NettyRemotingAbstract implements RemotingClient {
private static final Logger log = LoggerFactory.getLogger(RemotingHelper.ROCKETMQ_REMOTING);
private static final long LOCK_TIMEOUT_MILLIS = 3000;
private final NettyClientConfig nettyClientConfig;
private final Bootstrap bootstrap = new Bootstrap();
private final EventLoopGroup eventLoopGroupWorker;
private final Lock lockChannelTables = new ReentrantLock();
private final ConcurrentMap<String /* addr */, ChannelWrapper> channelTables = new ConcurrentHashMap<String, ChannelWrapper>();
private final Timer timer = new Timer("ClientHouseKeepingService", true);
private final AtomicReference<List<String>> namesrvAddrList = new AtomicReference<List<String>>();
private final AtomicReference<String> namesrvAddrChoosed = new AtomicReference<String>();
private final AtomicInteger namesrvIndex = new AtomicInteger(initValueIndex());
private final Lock lockNamesrvChannel = new ReentrantLock();
private final ExecutorService publicExecutor;
/**
* Invoke the callback methods in this executor when process response.
*/
private ExecutorService callbackExecutor;
private final ChannelEventListener channelEventListener;
private DefaultEventExecutorGroup defaultEventExecutorGroup;
private RPCHook rpcHook;
public NettyRemotingClient(final NettyClientConfig nettyClientConfig) {
this(nettyClientConfig, null);
}
public NettyRemotingClient(final NettyClientConfig nettyClientConfig,
final ChannelEventListener channelEventListener) {
super(nettyClientConfig.getClientOnewaySemaphoreValue(), nettyClientConfig.getClientAsyncSemaphoreValue());
this.nettyClientConfig = nettyClientConfig;
this.channelEventListener = channelEventListener;
int publicThreadNums = nettyClientConfig.getClientCallbackExecutorThreads();
if (publicThreadNums <= 0) {
publicThreadNums = 4;
}
this.publicExecutor = Executors.newFixedThreadPool(publicThreadNums, new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "NettyClientPublicExecutor_" + this.threadIndex.incrementAndGet());
}
});
this.eventLoopGroupWorker = new NioEventLoopGroup(1, new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, String.format("NettyClientSelector_%d", this.threadIndex.incrementAndGet()));
}
});
if (nettyClientConfig.isUseTLS()) {
try {
sslContext = TlsHelper.buildSslContext(true);
log.info("SSL enabled for client");
} catch (IOException e) {
log.error("Failed to create SSLContext", e);
} catch (CertificateException e) {
log.error("Failed to create SSLContext", e);
throw new RuntimeException("Failed to create SSLContext", e);
}
}
}
private static int initValueIndex() {
Random r = new Random();
return Math.abs(r.nextInt() % 999) % 999;
}
@Override
public void start() {
this.defaultEventExecutorGroup = new DefaultEventExecutorGroup(
nettyClientConfig.getClientWorkerThreads(),
new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "NettyClientWorkerThread_" + this.threadIndex.incrementAndGet());
}
});
Bootstrap handler = this.bootstrap.group(this.eventLoopGroupWorker).channel(NioSocketChannel.class)
.option(ChannelOption.TCP_NODELAY, true)
.option(ChannelOption.SO_KEEPALIVE, false)
.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, nettyClientConfig.getConnectTimeoutMillis())
.option(ChannelOption.SO_SNDBUF, nettyClientConfig.getClientSocketSndBufSize())
.option(ChannelOption.SO_RCVBUF, nettyClientConfig.getClientSocketRcvBufSize())
.handler(new ChannelInitializer<SocketChannel>() {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
if (nettyClientConfig.isUseTLS()) {
if (null != sslContext) {
pipeline.addFirst(defaultEventExecutorGroup, "sslHandler", sslContext.newHandler(ch.alloc()));
log.info("Prepend SSL handler");
} else {
log.warn("Connections are insecure as SSLContext is null!");
}
}
pipeline.addLast(
defaultEventExecutorGroup,
new NettyEncoder(),
new NettyDecoder(),
new IdleStateHandler(0, 0, nettyClientConfig.getClientChannelMaxIdleTimeSeconds()),
new NettyConnectManageHandler(),
new NettyClientHandler());
}
});
this.timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
try {
NettyRemotingClient.this.scanResponseTable();
} catch (Throwable e) {
log.error("scanResponseTable exception", e);
}
}
}, 1000 * 3, 1000);
if (this.channelEventListener != null) {
this.nettyEventExecutor.start();
}
}
//......
}- NettyRemotingClient使用了NettyClientConfig的相關配置來初始化NettyClient
- ChannelOption.CONNECT_TIMEOUT_MILLIS使用的是nettyClientConfig.getConnectTimeoutMillis()
- ChannelOption.SO_SNDBUF使用的是nettyClientConfig.getClientSocketSndBufSize()
- ChannelOption.SO_RCVBUF使用的是nettyClientConfig.getClientSocketRcvBufSize()
- IdleStateHandler的allIdleTimeSeconds參數使用的是nettyClientConfig.getClientChannelMaxIdleTimeSeconds()
小結
rocketmq的NettyClientConfig指定了NettyRemotingClient相關參數，這裏除了Netty相關的，還指定了兩個信號量，一個是clientOnewaySemaphoreValue，一個是clientAsyncSemaphoreValue。clientOnewaySemaphoreValue指定的是invokeOnewayImpl方法的調用控制，clientAsyncSemaphoreValue指定的是invokeAsyncImpl方法的調用頻率。
doc
- NettyClientConfig