我用netty编写了一个客户端，以便以高速率发送消息。通过 jConsole，我看到“老一代”正在增加，最后它抛出 java.lang.OutOfMemoryError: GC 开销限制超出。是否有一些方法或配置可以避免这个异常以下是我的测试代码：
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringEncoder;
import java.io.IOException;
import java.net.UnknownHostException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
public class TestNettyTcp {
private EventLoopGroup group;
private Channel ch;
/**
* @param args
* @throws SyslogSenderException
* @throws TimeoutException
* @throws ExecutionException
* @throws IOException
* @throws InterruptedException
* @throws UnknownHostException
*/
public static void main( String[] args )
throws UnknownHostException, InterruptedException, IOException, ExecutionException, TimeoutException {
new TestNettyTcp().testSendMessage();
}
public TestNettyTcp()
throws InterruptedException {
group = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group( group ).channel( NioSocketChannel.class )
// .option( ChannelOption.WRITE_BUFFER_HIGH_WATER_MARK, 10 * 64 * 1024 )
.option( ChannelOption.SO_RCVBUF, 1048576 ).option( ChannelOption.SO_SNDBUF, 1048576 )
.option( ChannelOption.TCP_NODELAY, true ).handler( new NettyTcpSyslogSenderInitializer() );
// Connect to a server.
ChannelFuture future = b.connect( "192.168.22.70", 514 );
future.awaitUninterruptibly();
// Now we are sure the future is completed.
assert future.isDone();
if ( !future.isSuccess() ) {
future.cause().printStackTrace();
}
else {
ch = future.sync().channel();
}
}
public void testSendMessage()
throws InterruptedException, UnknownHostException, IOException, ExecutionException, TimeoutException {
ThreadGroup threadGroup = new ThreadGroup( "SendMessage" );
for ( int k = 0; k < 10; k++ ) {
Thread thread = new Thread( threadGroup, new Runnable() {
@Override
public void run() {
String payLoad = "key=\"value\" key2=\"value2\" key3=\"value3\" Count:";
try {
for ( int j = 0; j < 100; j++ ) {
long a = System.currentTimeMillis();
for ( int i = 0; i < 20000; i++ ) {
ch.writeAndFlush( payLoad + j + "_" + i + "\n" );
}
System.out.println( "\r<br>Excuted time : " + ( System.currentTimeMillis() - a ) / 1000f
+ "seconde" );
}
}
catch ( InterruptedException e ) {
e.printStackTrace();
}
finally {
if ( ch != null ) {
ch.close();
}
}
}
} );
thread.start();
}
while ( threadGroup.activeCount() > 0 ) {
try {
Thread.sleep( 1000 );
}
catch ( InterruptedException e ) {
e.printStackTrace();
}
}
}
}
class NettyTcpSyslogSenderInitializer
extends ChannelInitializer<SocketChannel> {
public NettyTcpSyslogSenderInitializer() {
super();
}
@Override
public void initChannel( SocketChannel ch )
throws Exception {
ChannelPipeline pipeline = ch.pipeline();
pipeline.addLast( new StringEncoder() );
}
}
代码可以快速重现问题