Eclipse Tyrus is the open source JSR 356 - Java API for WebSocket
...Therefore Tyrus and WebSocket in general are suitable for web applications that require sending a huge volume of relatively small messages like online games or market ticker broadcasting.
...YourKit is kindly supporting this open source project with its full-featured Java Profiler. YourKit, LLC is the creator of innovative and intelligent tools for profiling Java and .NET applications. CentOS, 1 CPU, 4GB RAM runned on VM, CPU 10%, Memory 15%, 6000 xhr-long polling sessions or 15000 websockets sessions, 4000 messages per second.