Luxun - A high-throughput, persistent, distributed, publish-subscribe messaging system based on memo

A high-throughput, persistent, distributed, publish-subscribe messaging system based on memory mapped file and Thrift RPC.

Its design objectives are:

1. Fast: close to the speed of direct memory access, both produding and consuming are close to O(1) memory access.
2. Persistent : all data in the system is persisted on disk and is crash resistant.
3. High-throughput: even with modest hardware Luxun can support handreds of thousands of messages per second.
4. Realtime : messages produced by producer threads should be immediately visible to consumer threads.
5. Distributed : explicit support for partitioning messages over Luxun servers and distributing consumption over a cluster of consumer machines while maintaining per-partition ordering semantics.
6. Multiple clients support : use Thrift RPC as communication infrastructure, easy to generate different clients for different platforms.
7. Flexible consuming semantics : supports typical consume once queue, fan out queue, even supports consume by index when needed.