Phantom is a high performance proxy for accessing distributed services. It is an RPC system with support for different transports and protocols. Phantom is inspired by Twitter Finagle clients and builds on the capabilities of technologies like Netty, Unix Domain Sockets, Netflix Hystrix and Spring. Phantom proxies have been used to serve several hundred million API calls in production deployments at Flipkart.
Using Hystrix 1.5.8 Customizable core and max thread pool sizes for task handlers. See https://github.com/Netflix/Hystrix/issues/1242 and https://groups.google.com/forum/#!topic/hystrixoss/lT4CZgt-KRk for more details.