[undertow-dev] Undertow configuration

[Sascha Sadat-Guscheh]

Hi!

We want to use undertow in the following scenario (numbers are from our current app running jetty as a front end):

- 24 core machine with ~60GB ram
- 10000 requests per second with an average execution time of 2-4 ms
- around 6000 concurrent http connections (keep-alive)
- incoming request size between 2000 and 4000 bytes
- response size around 4000 bytes

At the moment we just copied the configuration from the Undertow class (using a HttpOpenListener).

OptionMap socketOptions = OptionMap.builder()
        .set(Options.WORKER_IO_THREADS, IO_THREADS)
        .set(Options.TCP_NODELAY, true)
        .set(Options.REUSE_ADDRESSES, true)
        .set(Options.BALANCING_TOKENS, 1)
        .set(Options.BALANCING_CONNECTIONS, 2)
        .set(Options.BACKLOG, 1000)
        .getMap();

OptionMap undertowOptions = OptionMap.builder().set(UndertowOptions.BUFFER_PIPELINED_DATA, true).getMap();
ByteBufferPool buffers = new DefaultByteBufferPool(true, 1024 * 16, -1, 4);
HttpOpenListener openListener = new HttpOpenListener(buffers, undertowOptions);

worker = xnio.createWorker(OptionMap.builder()
	        .set(Options.WORKER_IO_THREADS, IO_THREADS)
	        .set(Options.CONNECTION_HIGH_WATER, 1000000)
	        .set(Options.CONNECTION_LOW_WATER, 1000000)
	        .set(Options.WORKER_TASK_CORE_THREADS, IO_THREADS * 8)
	        .set(Options.WORKER_TASK_MAX_THREADS, IO_THREADS * 8)
	        .set(Options.TCP_NODELAY, true)
	        .set(Options.CORK, true)
	        .getMap());

Some of the options i don’t understand fully (BALANCING_TOKENS, BALANCING_CONNECTIONS) some may not be applicable to our scenario.
I dug around in the code a bit to find out what these settings do but i don’t feel very confident. A little help would be appreciated! 

Enjoy your holidays, Sascha