Redis

• redis/redis
  • RSALv2, SSPLv1, C
  • 7.2 BSD-3 -> RSALv2, SSPLv1
  • BSD fork
    • valkey
    • https://codeberg.org/redict/redict
• 支持的数据类型: string, bitmap, hll, list, pub/sub, hash, set, sorted set, stream
• Redis Stack 扩展: bloom, cuckoo, count-min, graph, json, suggest, search, t-digest, timeserial, top-k
• 参考
  • 5 Key Takeaways for Developing with Redis
    1. Keep Track of Your Keys
    2. Keep Track of the Length of Your Key Names
    3. Use the Right Data Structures
    4. Use SCAN, Never Use KEYS
    5. Use Server-Side Lua Scripts
  • Redis configuration for production
    • YouTube
• RedisGraph
  • A graph database as a Redis module

# 使用配置文件启动
wget http://download.redis.io/redis-stable/redis.conf
redis-server redis.conf
# macOS 安装
brew install redis
# 通过 docker 启动
# 数据存储于 ~/data/redis
docker run --rm -it -v $PWD/data:/data -p 6379:6379 --name redis redis redis-server --appendonly ye

redis-server --bind=0.0.0.0

info

• HASH Key 不支持 TTL #6620
  • keydb 可以 - 但是没有事件
• Redis Cluster V2 project redis#8948
• HSETEX, HMSETEX redis#2905
• 批量删除 key redis#4153

commands

# 获取 key 数量 - 可能失效的也包含
dbsize
# 获取 key 信息
info keyspace

# 扫描 key - SCAN,SSCAN,HSCAN,ZSCAN
# SCAN cursor [MATCH pattern] [COUNT count] [TYPE type]
scan 0

# NX -> Not Exists - 不存在则设置
# XX -> Exists - 存在则设置
# GET -> 返回旧值
# EX -> Expires Seconds - 过期时间 单位秒
# PX -> Expires Milliseconds - 过期时间 单位毫秒
# EXAT -> Expires At - 过期时间 时间戳秒
# PXAT -> Expires At - 过期时间 时间戳毫秒
# KEEPTTL -> 保持原有 TTL
SET key value [NX | XX] [GET] [EX seconds | PX milliseconds | EXAT unix-time-seconds | PXAT unix-time-milliseconds | KEEPTTL]

• 2.6.12+ 支持 EX, PX, NX, XX
• 6.0.0+ 支持 KEEPTTL
• 6.2.0+ 支持 GET, EXAT, PXAT
• 7.0.0+ 支持 NX, GET 同时使用

command	note
SETEX	-> SET key value EX seconds
SETNX	-> SET key value NX
PSETEX	-> SET key value PX milliseconds
GETSET	-> SET key value GET

Stream

• redis api
• 参考
  • Redis Streams: consumer groups v2 specification document
  • An update on Redis Streams development

命令

• L - List
• H - Hash
• Z - SortedSet
• S - Set
• X - Stream
• Channel - SUBSCRIBE,PUBLISH,UNSUBSCRIBE
  • P - Pattern - PSUBSCRIBE,PUNSUBSCRIBE
  • S - Shared - 集群 channel

Module

• 写 Redis 模块的教程
• Redis 模块仓库
• Antirez 关于 Redis 模块的博客
• wenerme/go-rm
  • 使用 Golang 写 Redis 模块

键变化通知

• 配置 notify-keyspace-events
  • 默认为 空 - 无事件产生
  • 可配置为 KEA 产生大多数事件
• __keyspace@<db>__:<key> event
  • key 变化
  • key -> event
• __keyevent@<db>__:<key> event
  • 事件
  • event -> key

| flag | | ---- | ----------------------------------- | | K | __keyspace@<db>__ 前缀 | | E | __keyevent@<db>__ 前缀 | | g | 通用命令 - DEL, EXPIRE, RENAME, ... | | $| string | | l | list | | s | set | | h | hash | | z | Sorted set | | t | stream | | d | module key type | | x | expired events | | e | evicted events | | m | key miss events - 访问不存在的 KEY | | n | new key events - A 不包含 | | A | `g$lshztxed` - 除了 mn 的所有事件 |

evennt	command
del	DEL,MIGRATE,RPOP,LPOP
rename_from,rename_to	RENAME
move_from,move_to	MOVE
copy_to	COPY
restore	RESTORE
expire	EXPIRE,SETEX
sortstore	SORT STORE
set	SET,MSET
setrange	SETRANG
incrby	INCR, DECR, INCRBY, DECRBY
incrbyfloat	INCRBYFLOAT
append
lpush
rpush
rpop
lpop
linsert
lrem
ltrim
hset	HSET, HSETNX, HMSET
hincrby
hincrbyfloat
hdel
sadd	SADD,SMOVE
srem	SREM,SMOVE
spop
sinterstore
sunionstore
sdiffstore
zincr
zadd
zrem
zrembyscore
zrembyrank
zdiffstore
zinterstore
zunionstore
xadd
xdel
xgroup-create
xgroup-destroy
xgroup-setid
xgroup-setid
xsetid
xtrim
xgroup-createconsumer
xgroup-delconsumer
persist

• {l,r}{pop,push}
  • RPOPLPUSH, BRPOPLPUSH
  • LMOVE, BLMOVE
• expired
• evicted
• new

# 所有事件
redis-cli --csv psubscribe '__key*__:*'

redis-benchmark

redis-benchmark -q -n 100000
redis-benchmark -q -n 100000 -t set,get -P 16

• https://redis.io/docs/reference/optimization/benchmarks/

Inside