老男孩Python全栈6期——redis
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Linux 操做系统 默认的内存管理机制
RSS:
page cache:
anno page:
Linux操做系统以page进行分配内存,page大小默认4K
slab allocator 内存页的划分
buddy system :LRU 最近最少使用原则
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redis
在单用户多并发读写,性能高
在多用户少读写时,memcache更优
redis是一个单核的管理机制,生产中通常是,单机多实例的架构。
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redis配置文件:
vim /etc/redis.confpython
是否后台运行:
daemonize no/yes
默认端口:
port 6379
AOF日志开关是否打开:
appendonly no/yes
日志文件位置
logfile /var/log/redis.log
RDB持久化数据文件:
dbfilename dump.rdbgit
daemonize yes
port 6379
dbfilename dump.rdb
dir "/application/data/6379"
logfile /var/log/redis.loggithub
cd /root
vim .bash_profile
PATH 行添加
:/application/redis-3.2.6/srcredis
配置生效
source .bash_profilevim
配置完成以后,能够直接在命令行调用redis命令安全
例如:
redis-cli
shutdown
redis-server /etc/redis.confruby
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安全控制
vim /etc/redis.conf bash
bind 10.0.0.200
requirepass root服务器
关闭redis
redis-cli
shutdown
启动redis
redis-server /etc/redis.conf
链接redis:
设置完成以后须要换种打开方式:
redis-cli -h 10.0.0.200 -a root
-h <hostname>
-p <port>
-a <password>
redis-cli 默认状况是如下的方式链接
redis-cli -h 127.0.0.1 -p 6379
因此须要加上-h -a 选项
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在线变动配置:
获取当前配置
CONFIG GET *
变动运行配置
CONFIG SET loglevel "notice"
例子:修改密码
CONFIG SET requirepass "123"
CONFIG GET requirepass
在线修改的配置,下次登陆生效,可是重启以后配置会丢失。
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import redis
r = redis.StrictRedis(host='10.0.0.200', port=6379, db=0)
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redis持久化功能
RDB:快照,只记录一个时刻内存数据状态
配置:
dbfilename dump.rdb
dir "/application/data/6379"
save 900 1
save 300 10
save 60 10000
配置分别表示:
• 900秒(15分钟)内有1个更改
• 300秒(5分钟)内有10个更改
• 60秒内有10000个更改
扩展选项:
stop-writes-on-bgsave-error yes
rdbcompression yes
rdbchecksum yes
AOF:只追加日志文件,记录了redis中全部的修改命令
配置:
appendonly yes
appendfsync everysec
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数据类型
5中
发布订阅
SUBSCRIBE weibo 订阅一个频道
PSUBSCRIBE * 订阅多个频道
PSUBSCRIBE beijing.* 订阅全部和北京相关的频道
PUBLISH weibo hello
ZADD salary 2000 user1
ZADD salary 3000 user2
ZRANGE salary 0 -1 WITHSCORES
MULTI
ZINCRBY salary 1000 user1
ZINCRBY salary -1000 user2
EXEC
Info
Clinet list
Client kill ip:port
config get *
CONFIG RESETSTAT 重置统计
CONFIG GET/SET 动态修改
Dbsize
FLUSHALL 清空全部数据
select 1
FLUSHDB 清空当前库
MONITOR 监控实时指令
SHUTDOWN 关闭服务器
save将当前数据保存
SLAVEOF host port 主从配置
SLAVEOF NO ONE
SYNC 主从同步
ROLE返回主从角色
CONFIG SET slowlog-log-slower-than 100
CONFIG SET slowlog-max-len 1000
CONFIG GET slow*
SLOWLOG GET
SLOWLOG RESET
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主从复制
一、故障转移 failover
二、分担负载 blance
搭建主从
准备2个以上的redis实例
一、多配置文件(端口、数据路径、日志路径、pid)
端口:
6380(主)
6381(从)
数据路径(持久化文件存放位置):
/application/data/6380
/application/data/6381
日志路径:
/var/log/redis6380.log
/var/log/redis6381.log
pid文件
/application/data/6380/redis.pid
/application/data/6381/redis.pid
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配置过程
一、建立目录:
mkdir -p /application/data/6380
mkdir -p /application/data/6381
二、配置文件准备
vim /application/data/6380/redis.conf
port 6380
daemonize yes
pidfile /application/data/6380/redis.pid
logfile "/var/log/redis6380.log"
dbfilename dump.rdb
dir /application/data/6380
vim /application/data/6381/redis.conf
port 6381
daemonize yes
pidfile /application/data/6381/redis.pid
logfile "/var/log/redis6381.log"
dbfilename dump.rdb
dir /application/data/6381
三、启动两个实例
redis-server /application/data/6380/redis.conf
redis-server /application/data/6381/redis.conf
四、构建主从
redis-cli -p 6381
slaveof 127.0.0.1 6380
五、验证主从
登陆主库:
redis-cli -p 6380
set foo bar
登陆主库:
redis-cli -p 6381
get
六、主从复制状态查看。
role
info replication
七、主从复制,手工切换
slaveof no one
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传统主从的缺陷
一、没有自动监控机制
二、没有自动切换的功能
三、对于应用不透明
sentinel 功能
一、自动监控redis全部节点状态
二、发现主库故障,自动选主切换
三、自动通知应用端
准备,1主2从结构比较合适。
添加6382节点:
mkdir -p /application/data/6382
vim /application/data/6382/redis.conf
port 6382
daemonize yes
pidfile /application/data/6382/redis.pid
logfile "/var/log/redis6382.log"
dbfilename dump.rdb
dir /application/data/6382
redis-server /application/data/6382/redis.conf
redis-cli -p 6382
slaveof 127.0.0.1 6380
sentinel配置
mkdir -p /application/data/26380
vim /application/data/26380/sentinel.conf
port 26380
dir "/application/data/26380"
sentinel monitor mymaster 127.0.0.1 6380 1
sentinel down-after-milliseconds mymaster 60000
sentinel config-epoch mymaster 0
启动
redis-sentinel /application/data/26380/sentinel.conf
+++++++++++++++++Python sentinel+++++++++++++++++
>>> from redis.sentinel import Sentinel
>>> sentinel = Sentinel([('127.0.0.1', 26380)], socket_timeout=0.1)
>>> sentinel.discover_master('mymaster')
('127.0.0.1', 6379)
>>> sentinel.discover_slaves('mymaster')
[('127.0.0.1', 6380)]
>>> master = sentinel.master_for('mymaster', socket_timeout=0.1)
>>> slave = sentinel.slave_for('mymaster', socket_timeout=0.1)
>>> master.set('foo', 'bar')
>>> slave.get('foo')
'bar'
++++++++++++++++++++++++++++++++++
redis 分片cluser 部署
一、集群组件安装
EPEL源安装ruby支持
yum install ruby rubygems -y
使用国内源
gem sources --add https://gems.ruby-china.org/ --remove https://rubygems.org/
若是没法使用,可使用aliyun
gem sources -a http://mirrors.aliyun.com/rubygems/
gem sources --remove http://rubygems.org/
gem sources -l
gem install redis -v 3.3.3
二、集群节点准备
规划:
端口:7000-7005
路径:
/application/data/7000
/application/data/7001
/application/data/7002
/application/data/7003
/application/data/7004
/application/data/7005
日志路径:
/var/log/redis7000.log
/var/log/redis7001.log
/var/log/redis7002.log
/var/log/redis7003.log
/var/log/redis7004.log
/var/log/redis7005.log
pid文件
/application/data/7000/redis.pid
/application/data/7001/redis.pid
/application/data/7002/redis.pid
/application/data/7003/redis.pid
/application/data/7004/redis.pid
/application/data/7005/redis.pid
建立节点目录:
mkdir -p /application/data/7000
mkdir -p /application/data/7001
mkdir -p /application/data/7002
mkdir -p /application/data/7003
mkdir -p /application/data/7004
mkdir -p /application/data/7005
配置文件添加:
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vim /application/data/7000/redis.conf
port 7000
daemonize yes
pidfile /application/data/7000/redis.pid
logfile "/var/log/redis7000.log"
dbfilename dump.rdb
dir /application/data/7000
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
vim /application/data/7001/redis.conf
port 7001
daemonize yes
pidfile /application/data/7001/redis.pid
logfile "/var/log/redis7001.log"
dbfilename dump.rdb
dir /application/data/7001
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
vim /application/data/7002/redis.conf
port 7002
daemonize yes
pidfile /application/data/7002/redis.pid
logfile "/var/log/redis7002.log"
dbfilename dump.rdb
dir /application/data/7002
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
vim /application/data/7003/redis.conf
port 7003
daemonize yes
pidfile /application/data/7003/redis.pid
logfile "/var/log/redis7003.log"
dbfilename dump.rdb
dir /application/data/7003
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
vim /application/data/7004/redis.conf
port 7004
daemonize yes
pidfile /application/data/7004/redis.pid
logfile "/var/log/redis7004.log"
dbfilename dump.rdb
dir /application/data/7004
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
vim /application/data/7005/redis.conf
port 7005
daemonize yes
pidfile /application/data/7005/redis.pid
logfile "/var/log/redis7005.log"
dbfilename dump.rdb
dir /application/data/7005
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
启动全部节点
redis-server /application/data/7000/redis.conf
redis-server /application/data/7001/redis.conf
redis-server /application/data/7002/redis.conf
redis-server /application/data/7003/redis.conf
redis-server /application/data/7004/redis.conf
redis-server /application/data/7005/redis.conf
ps -ef |grep 700
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三、集群建立
redis-trib.rb create --replicas 1 127.0.0.1:7000 127.0.0.1:7001 \
127.0.0.1:7002 127.0.0.1:7003 127.0.0.1:7004 127.0.0.1:7005
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四、集群状态查看
redis-cli -p 7000 cluster nodes | grep master
+++++++++++++++Python 链接 redis cluster+++++++++++++++++(1) redis-py并无提供redis-cluster的支持,去github找了一下,有个叫redis-py-cluster的源码,可是和redis-py不是一个做者,地址为:https://github.com/Grokzen/redis-py-clusterwatch,star,fork还算能够。(2) 安装 Latest stable release from pypi$ pip install redis-py-cluster or from source$ python setup.py install(3) 使用>>> from rediscluster import StrictRedisCluster >>> startup_nodes = [{"host": "127.0.0.1", "port": "7000"}] >>> # Note: decode_responses must be set to True when used with python3 >>> rc = StrictRedisCluster(startup_nodes=startup_nodes, decode_responses=True) >>> rc.set("foo", "bar") True >>> print(rc.get("foo")) 'bar'++++++++++++++++++++++++++++++++