Pedis (Parallel Redis)

What's Pedis?

Pedis is the NoSQL data store using the SEASTAR framework, compatible with REDIS. The name of Pedis is an acronym of Parallel redis, which with high throughput and low latency.

Redis is very popular data structures server. For more infomation, see here: http://redis.io/ Seastar is an advanced, open-source C++ framework for high-performance server applications on modern hardware. For more infomation, see here: http://www.seastar-project.org/

Now, the redis commands were supported by Pedis as follow:

• KEY: DEL, EXISTS, TTL, PTTL, EXPIRE, PEXPIRE
• STRING: GET, SET, DECR, INCR, DECRBY, INCRBY, APPEND, STRLEN, MGET, MSET
• LIST: LINDEX, LINSERT, LLEN, LPUSH, LPUSHX, LPOP, LRANGE, LREM, LTRIM, LSET, RPOP, RPUSH, RPUSHX
• HASH: HSET, HDEL, HGET, HLEN, HSTRLEN, HMSET, HMGET, HKEYS, HVALS, HEXISTS, HINCRBY
• SET: SADD, SMEMBERS, SISMEMBER, SREM, SDIFF, SDIFFSTORE, SINTER, SINTERSTORE, SUNION, SUNIONSTORE, SMOVE, SPOP
• SORTED SET: ZADD, ZCARD, ZCOUNT, ZINCRBY, ZRANGE, ZRANK, ZREM, ZREMRANGEBYSCORE, ZREMRANGEBYRANK, ZREVRANGE, ZREVRANGEBYSCORE, ZREVRANK, ZSCORE, ZUNIONSTORE, ZINTERSTORE
• GEO: GEOADD, GEOPOS, GEOHASH, GEODIST, GEORADIUS, GEORADIUSMEMBER
• HyperLogLog: PFADD, PFCOUNT, PFMERGE
• OTHER: ECHO, PING, SELECT

Building Pedis

In fact, the building instructions of Seastar also works for Pedis.

See building instructions for Fedora, CentOS and Ubuntu.

Getting started

./build/release/pedis --c 1 -m 1G

Current Roadmap

We will build the next generation of redis cluster.

Short-term

• Implement the redis commands.
• Output the necessary metrics.

Long-term

• Build the redis cluster, using GOSSIP protocol to broadcast redis node's status.
• Build the data replication mechanism between redis cluster.
• Persist the data to disk based on Structured-logs-merged tree.

Benchmark

The following describe the details of the Pedis benchmark making it reproducible. The result data was generated by memtier_benchmark(https://github.com/RedisLabs/memtier_benchmark).

Latest Results(Sep. 2016)

Pedis's latency was less then 0.5ms for 99% of all requests.

Test bed:

• Server 1: Pedis/Redis Server
• Server 2: memtier_benchmark tool

Software:

• OS RedHat EL7
• Pedis (latest)
• Redis (2.8)

Hardware:

• Memory: 128GB
• SSD: 500GB
• CPU: 24 logical cores
• NIC: 1000Mb