本文介紹系統緩存組件,採用NOSQL之Redis做爲系統緩存層。node
1、背景c++
系統考慮到高併發的使用場景。對於併發提交場景,經過上一章節介紹的RabbitMQ組件解決。對於系統高併發查詢,爲了提供性能減小數據庫壓力,咱們加入緩存機制,能夠不一樣層次加入緩存支持,本文主要介紹應用服務層和數據層之間加入緩存機制提高性能。業界緩存組件有Redis、Memcached、MemoryCache。本系統採用Redis緩存組件,有些系統將Redis看成MQ使用,此場景本系統用RabbitMQ,Redis主要用於系統緩存應用。redis
2、Redis簡介數據庫
Redis是一個開源的Key-Value數據庫,使用C語言編寫、支持網絡、可基於內存亦可持久化的NOSQL數據庫,並提供多種語言的API,例如:Java,C/C++,C#,PHP,JavaScript,Perl,Object-C,Python,Ruby等語言驅動。自Redis3.0開始支持集羣方案。vim
相關Redis Cluster 原理在此很少介紹,網絡上有不少資料。windows
3、Redis集羣應用centos
(一)環境介紹設計模式
本系統基於Linux之CentOS搭建Redis3.0集羣。將三個Instance部署於一臺虛擬機,應用部署於windows平臺。緩存
序號 | 服務IP | 說明 |
1 | 192.168.1.110 | Redis節點A端口:7000(M),7003(S)ruby Redis節點B端口:7001(M),7004(S) Redis節點C端口:7002(M),7005(S) |
(二)安裝Redis
一、安裝相關依賴工具
[root@andoncentos 桌面]# yum -y install gcc openssl-devel libyaml-devel libffi-devel readline-devel zlib-devel gdbm-devel ncurses-devel gcc-c++ automake autoconf
二、安裝Redis 3.0.6
[root@andoncentos 桌面]# cd /usr/loacal
[root@andoncentos loacal]# wget http://download.redis.io/releases/redis-3.0.6.tar.gz
[root@andoncentos 桌面]# tar xvf redis-3.0.6.tar.gz
[root@andoncentos 桌面]# cd redis-3.0.6/
[root@andoncentos 桌面]# make MALLOC=libc
[root@andoncentos redis-3.0.6]# make install
三、因爲咱們使用不一樣端口號區分,在兩個服務各自創建以端口命名的文件夾。配置7000節點服務,將redis-server和redis.conf複製到/etc/redis/7000
[root@andoncentos 桌面]# mkdir /etc/redis/7000
[root@andoncentos 桌面]# mkdir /etc/redis/7001
[root@andoncentos 桌面]# mkdir /etc/redis/7002
[root@andoncentos 桌面]# mkdir /etc/redis/7003
[root@andoncentos 桌面]# mkdir /etc/redis/7004
[root@andoncentos 桌面]# mkdir /etc/redis/7005
[root@andoncentos redis-3.0.6]# cp /usr/local/redis-3.0.6/src/redis-server /usr/local/redis-3.0.6/redis.conf /etc/redis/7000
[root@andoncentos redis-3.0.6]# vim /etc/redis/7000/redis.conf
port 7000
daemonize yes
pidfile /var/run/redis_7000.pid
cluster-enabled yes
cluster-config-file nodes.conf
logfile "/var/log/redisd7000.log"
dir /etc/redis/7000/
cluster-node-timeout 5000
appendonly yes
四、修改redis服務的啓動腳本,修改內容,並複製相關其餘的節點配置
[root@andoncentos redis-3.0.6]# cp /usr/local/redis-3.0.6/utils/redis_init_script /etc/init.d/redis7000 [root@andoncentos redis-3.0.6]# vim /etc/init.d/redis7000
#!/bin/sh
# chkconfig 2345 90 10
# description:Redis is a persistent key-value database
# Simple Redis init.d script conceived to work on Linux systems
# as it does use of the /proc filesystem.
REDISPORT=7000
# EXEC=/usr/local/bin/redis-server
EXEC=/etc/redis/${REDISPORT}/redis-server
CLIEXEC=/usr/local/bin/redis-cli
PIDFILE=/var/run/redis_${REDISPORT}.pid
CONF="/etc/redis/${REDISPORT}/redis.conf"
[root@andoncentos redis-3.0.6]# cp /etc/init.d/redis7000 /etc/init.d/redis7001 [root@andoncentos redis-3.0.6]# cp /etc/init.d/redis7000 /etc/init.d/redis7003 [root@andoncentos redis-3.0.6]# cp /etc/init.d/redis7000 /etc/init.d/redis7004
五、設置爲開機自啓動服務器
[root@andoncentos redis-3.0.6]# chkconfig redis7000 on [root@andoncentos redis-3.0.6]# chkconfig redis7001 on [root@andoncentos redis-3.0.6]# chkconfig redis7003 on [root@andoncentos redis-3.0.6]# chkconfig redis7004 on
六、重啓系統,並檢查redis7000,redis7001,redis7003,redis7004服務狀況
[root@andoncentos redis-3.0.6]# reboot
[root@andoncentos 桌面]# systemctl status redis7004.service
(三)配置Redis集羣
一、按照 ruby tree 工具,由於redis集羣須要ruby
[root@andoncentos redis-3.0.6]# yum -y install tcl ruby tree
[root@andoncentos 桌面]# gem install redis --version 3.0.6
Fetching: redis-3.0.6.gem (100%)
Successfully installed redis-3.0.6
Parsing documentation for redis-3.0.6
Installing ri documentation for redis-3.0.6
1 gem installed
二、redis-trib.rb 配置集羣
[root@andoncentos 桌面]# /usr/local/redis-3.0.6/src/redis-trib.rb create --replicas 1 192.168.1.110:7000 192.168.1.110:7001 192.168.1.110:7002 192.168.1.110:7003 192.168.1.110:7004 192.168.1.110:7005 >>> Creating cluster >>> Performing hash slots allocation on 6 nodes... Using 3 masters: 192.168.1.110:7000 192.168.1.110:7001 192.168.1.110:7002 Adding replica 192.168.1.110:7003 to 192.168.1.110:7000 Adding replica 192.168.1.110:7004 to 192.168.1.110:7001 Adding replica 192.168.1.110:7005 to 192.168.1.110:7002 M: b164701893bfbdc078e2f7e3b16f1216c1bf65ff 192.168.1.110:7000 slots:0-5460 (5461 slots) master M: 4c2d36c55cff692a7bbeccb663197b555747d15d 192.168.1.110:7001 slots:5461-10922 (5462 slots) master M: b147e4dfcd63c5ce059540db55a9d7cb9fa093eb 192.168.1.110:7002 slots:10923-16383 (5461 slots) master S: 757381aa5cc5c8ba70f3798f6de6cb7b2e97f924 192.168.1.110:7003 replicates b164701893bfbdc078e2f7e3b16f1216c1bf65ff S: fecc8edf32fc72cd4a5d8ae5306fe4083abfe8e9 192.168.1.110:7004 replicates 4c2d36c55cff692a7bbeccb663197b555747d15d S: 98bd8e1aff631a3bee7f92a39764decea16ee955 192.168.1.110:7005 replicates b147e4dfcd63c5ce059540db55a9d7cb9fa093eb Can I set the above configuration? (type 'yes' to accept): yes >>> Nodes configuration updated >>> Assign a different config epoch to each node >>> Sending CLUSTER MEET messages to join the cluster Waiting for the cluster to join.... >>> Performing Cluster Check (using node 192.168.1.110:7000) M: b164701893bfbdc078e2f7e3b16f1216c1bf65ff 192.168.1.110:7000 slots:0-5460 (5461 slots) master M: 4c2d36c55cff692a7bbeccb663197b555747d15d 192.168.1.110:7001 slots:5461-10922 (5462 slots) master M: b147e4dfcd63c5ce059540db55a9d7cb9fa093eb 192.168.1.110:7002 slots:10923-16383 (5461 slots) master M: 757381aa5cc5c8ba70f3798f6de6cb7b2e97f924 192.168.1.110:7003 slots: (0 slots) master replicates b164701893bfbdc078e2f7e3b16f1216c1bf65ff M: fecc8edf32fc72cd4a5d8ae5306fe4083abfe8e9 192.168.1.110:7004 slots: (0 slots) master replicates 4c2d36c55cff692a7bbeccb663197b555747d15d M: 98bd8e1aff631a3bee7f92a39764decea16ee955 192.168.1.110:7005 slots: (0 slots) master replicates b147e4dfcd63c5ce059540db55a9d7cb9fa093eb [OK] All nodes agree about slots configuration. >>> Check for open slots... >>> Check slots coverage... [OK] All 16384 slots covered.
三、檢查集羣狀態
[root@andoncentos 桌面]# /usr/local/redis-3.0.6/src/redis-trib.rb check 192.168.1.110:7000
四、若出錯的話,經過以下命令行修復
[root@andoncentos 桌面]# /usr/local/redis-3.0.6/src/redis-trib.rb fix 192.168.1.110:7000
五、防火牆開放端口,並重啓防火牆
[root@andoncentos 桌面]# firewall-cmd --zone=public --add-port=7000-7005/tcp --permanent success [root@andoncentos 桌面]# firewall-cmd --reload success
六、檢查集羣狀況
[root@andoncentos 桌面]# redis-cli -c -p 7000 127.0.0.1:7000> cluster info cluster_state:ok cluster_slots_assigned:16384 cluster_slots_ok:16384 cluster_slots_pfail:0 cluster_slots_fail:0 cluster_known_nodes:6 cluster_size:3 cluster_current_epoch:6 cluster_my_epoch:1 cluster_stats_messages_sent:2492 cluster_stats_messages_received:2492
4、使用說明
(一)使用命令行測試緩存
(二)經過C#代碼測試緩存
一、經過使用stackexchang.redis組件,將數據緩存到集羣redis服務。
var cfg = RedisCachingSectionHandler.GetConfig(); var serializer = new NewtonsoftSerializer(); var redis = new StackExchangeRedisCacheClient(serializer, cfg); var cls = new Cls(){ ID = 1, Name = txt }; string key = "tkey" + new Random().Next(1000, 9999).ToString(); redis.Add<Cls>(key, cls);
二、經過key獲取數據
var cfg = RedisCachingSectionHandler.GetConfig(); var serializer = new NewtonsoftSerializer(); var redis = new StackExchangeRedisCacheClient(serializer, cfg); var entity = redis.Get<Cls>(key); ViewBag.KV = entity != null ? entity.Name : "";
三、redis緩存狀況
5、總結
redis cluster 默認支持HA,可是對於單個Instance故障,使用者須要自行判斷處理的機制,後續有待於研究,可是redis codis 這方面提供了方便的支持。