Dragonboat is a high performance multi-group Raft consensus library in Go with C++11 binding support.

Consensus algorithms such as Raft provides fault-tolerance by alllowing a system continue to operate as long as the majority member servers are available. For example, a Raft cluster of 5 servers can make progress even if 2 servers fail. It also appears to clients as a single node with strong data consistency always provided. All running servers can be used to initiate read requests for aggregated read throughput.

Dragonboat handles all technical difficulties associated with Raft to allow users to just focus on their application domains. It is also very easy to use, our step-by-step examples can help new users to master it in half an hour.

Most features covered in Diego Ongaro's Raft thesis have been supported -

Dragonboat is the fastest open source multi-group Raft implementation on Github.

For 3-nodes system using mid-range hardware, e.g. 22 cores Intel Xeon at 2.8Ghz and enterprise NVME SSD (details here), Dragonboat can sustain at 9 million writes per second when the payload is 16bytes each or 11 million mixed I/O per second at 9:1 read:write ratio. High throughput is maintained in geographically distributed environment. When the RTT between nodes is 30ms, 2 million I/O per second can still be achieved using a much larger number of clients.

The number of concurrent active Raft groups affects the overall throughput as requests become harder to be batched. On the other hand, having thousands of idle Raft groups has a much smaller impact on throughput.

Table below shows write latencies in millisecond, Dragonboat has