Herd

Reading“Using RDMA Efficiently

for Key-Value Services”[1]

@syoyo

Thursday, August 7, 14

Overview

• KVS(GET/PUT) + RDMA

• 26 million key-value op per second

• 5 us average latency

• 1 key-value item size <= 1024 bytes

• 2x faster than previous method


Previous work

• Pilaf : C. Mitchell, Y. Geng, and J. Li. Using One-Sided RDMA Reads to Build a Fast, CPU-Efficient Key-Value Store. In USENIX ATC, 2013.

• FaRM : A.Dragojevic,D.Narayanan,O.Hodson,andM.Castro. FaRM: Fast Remote Memory. In USENIX NSDI, 2014.

• MICA: H. Lim, D. Han, D. G. Andersen, and M. Kaminsky. MICA: A Holistic Approach to Fast In-Memory Key-Value Storage. In USENIX NSDI, 2014.


• Use RDMA WRITE instead of RDMA READ

• Half round trip latency


ServerClient

Client

RDMA WRITE UC

RDMA WRITE UCpolling

SEND UD

SEND UD


Op

• 1) client -> server request(PUT, GET) using RDMA WRITE

• 2) server polls per-client memory region to check request

• 3) Do key-value lookup

• 4) server -> client reply using SEND


Evaluation

• Apt

• IB FDR(56 Gbps) ConnectX-3

• Susitna

• RoCE(40GbE CX-3 MX313A)


References

• [1] https://www.cs.cmu.edu/~akalia/doc/herd_readable.pdf

• https://github.com/efficient/HERD


https://www.cs.cmu.edu/~akalia/doc/herd_readable.pdf




https://github.com/efficient/HERD

https://github.com/efficient/HERD

Herd

Technology

Transcript of Herd