I use Netty for a multithreaded TCP server and a single client persistent connection. The client sends many binary messages (10000 in my use case) and is supposed to receive an answer for each message. I added an OrderedMemoryAwareThreadPoolExecutor to the pipeline to handle the execution of DB calls on multiple threads.
If I run a DB call in the method messageReceived() (or simulate it with Thread.currentThread().sleep(50)) then all events are handled by a single thread.
5 count of {main}
1 count of {New
10000 count of {pool-3-thread-4}
For a simple implementation of messageReceived() the server creates many executor threads as expected.
How should I configure the ExecutionHandler to get multiple threads executors for the business logic, please?
Here is my code:
public class MyServer {
public void run() {
OrderedMemoryAwareThreadPoolExecutor eventExecutor = new OrderedMemoryAwareThreadPoolExecutor(16, 1048576L, 1048576L, 1000, TimeUnit.MILLISECONDS, Executors.defaultThreadFactory());
ExecutionHandler executionHandler = new ExecutionHandler(eventExecutor);
bootstrap.setPipelineFactory(new ServerChannelPipelineFactory(executionHandler));
}
}
public class ServerChannelPipelineFactory implements ChannelPipelineFactory {
public ChannelPipeline getPipeline() throws Exception {
pipeline.addLast("encoder", new MyProtocolEncoder());
pipeline.addLast("decoder", new MyProtocolDecoder());
pipeline.addLast("executor", executionHandler);
pipeline.addLast("myHandler", new MyServerHandler(dataSource));
}
}
public class MyServerHandler extends SimpleChannelHandler {
public void messageReceived(ChannelHandlerContext ctx, final MessageEvent e) throws DBException {
// long running DB call simulation
try {
Thread.currentThread().sleep(50);
} catch (InterruptedException ex) {
}
// a simple message
final MyMessage answerMsg = new MyMessage();
if (e.getChannel().isWritable()) {
e.getChannel().write(answerMsg);
}
}
}
