Mytec

Multi Selector threads in Grizzly 1.5

Default Grizzly Controller configuration uses single Selector thread for handling Channel events, it means OP_ACCEPT and OP_READ events are handled by a single Selector. For sure to process bigger number of concurrent requests - it's not enough, and we may need to spread Channels among several Selector threads.
It's very easy to do in Grizzly - Controller.setReadThreadsCount(threadNum);
It let's main (Controller) Selector thread to process only OP_ACCEPT events, and each accepted Channel will be registered for reading on a different Selector thread, taken from queue. Default Multi Selector threads implementation is working in RoundRobin manner.

Here is example, how to start Grizzly Controller with several Selector threads.
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
        final ProtocolFilter readFilter = new ReadFilter();
        final ProtocolFilter echoFilter = new EchoFilter();
       
        TCPSelectorHandler selectorHandler = new TCPSelectorHandler();
        selectorHandler.setPort(PORT);
        final Controller controller = new Controller();     
        controller.setReadThreadsCount(SELECTOR_THREADS_NUM);
        controller.setSelectorHandler(selectorHandler);
       
        controller.setProtocolChainInstanceHandler(
                new DefaultProtocolChainInstanceHandler(){
            public ProtocolChain poll() {
                ProtocolChain protocolChain = protocolChains.poll();
                if (protocolChain == null){
                    protocolChain = new DefaultProtocolChain();
                    protocolChain.addFilter(readFilter);
                    protocolChain.addFilter(echoFilter);
                }
                return protocolChain;
            }
        });

        controller.start();
/////////////////////////////////////////////////////////////////////////////////////////////////////////////

Posted at 05:24PM Jun 15, 2007 by oleksiys in Grizzly  |  Comments[5]