redis緩衝的使用總結

本人使用了redis3.0版本。3.0版本主要增加了redis叢集功能。

安裝的前提條件：安裝gcc：yum install gcc-c++

1、下載redis的源碼包。

2、把源碼包上傳到linux伺服器

3、解壓源碼包 tar -zxvf redis-3.0.0.tar.gz

4、Make

5、Make install

[root@shuang redis-3.0.0]# make install PREFIX=/usr/local/redis

1.1 啟動redis

1、前端啟動模式

/usr/local/redis/bin/redis-server

預設是前端啟動模式，連接埠是6379

2、後端啟動

1）從redis的源碼目錄中複製redis.conf到redis的安裝目錄。

2）修改設定檔redis.conf

3）[root@shuang bin]# ./redis-server redis.conf

1.2 redis的常用命令

127.0.0.1:6379> set a 10

OK

127.0.0.1:6379> get a

"10" 等等

1.3 redis常用資料類型

String

Hash

List

Set

SortedSet

1. 4Redis叢集的搭建

redis-cluster把所有的物理節點映射到[0-16383]slot上,cluster 負責維護node<->slot<->value

Redis 叢集中內建了 16384 個雜湊槽，當需要在 Redis 叢集中放置一個 key-value 時，redis 先對 key 使用 crc16 演算法算出一個結果，然後把結果對 16384 求餘數，這樣每個 key 都會對應一個編號在 0-16383 之間的雜湊槽，redis 會根據節點數量大致均等的將雜湊槽映射到不同的節點 例如：

Key:a

計算a的hash值，例如值為100，100這個槽在server1上，所以a應該放到server1.

 

Key:hello

Hash值：10032，此槽在server2上。Hell可以應該存在server2. 1.5 redis-cluster投票:容錯

(1)領著投票過程是叢集中所有master參與,如果半數以上master節點與master節點通訊超過(cluster-node-timeout),認為當前master節點掛掉.

(2):什麼時候整個叢集不可用(cluster_state:fail)? 

a:如果叢集任意master掛掉,且當前master沒有slave.叢集進入fail狀態,也可以理解成叢集的slot映射[0-16383]不完成時進入fail狀態.

 ps : redis-3.0.0.rc1加入cluster-require-full-coverage參數,預設關閉,開啟叢集相容部分失敗.

    b:如果叢集超過半數以上master掛掉，無論是否有slave叢集進入fail狀態.

  ps:當叢集不可用時,所有對叢集的操作做都不可用，收到((error) CLUSTERDOWN The cluster is down)錯誤

二 redis叢集

1.1 我的叢集結構

叢集中有三個節點的叢集，每個節點有一主一備。需要6台虛擬機器。

搭建一個偽分布式的叢集，使用6個redis執行個體來類比。

  1.2 搭建叢集需要的環境

搭建叢集需要使用到官方提供的ruby指令碼。

需要安裝ruby的環境。

 

安裝ruby

yum install ruby

yum install rubygems

 

redis叢集管理工具redis-trib.rb

[root@shuang ~]# cd redis-3.0.0

[root@shuang redis-3.0.0]# cd src

[root@shuang src]# ll *.rb

-rwxrwxr-x. 1 root root 48141 Apr  1 07:01 redis-trib.rb

[root@shuang src]#

 

指令碼需要的ruby包：

需要上傳到linux服務。

安裝ruby的包：

gem install redis-3.0.0.gem

[root@bogon ~]# gem install redis-3.0.0.gem

Successfully installed redis-3.0.0

1 gem installed

Installing ri documentation for redis-3.0.0...

Installing RDoc documentation for redis-3.0.0... 1.3 叢集的搭建

第一步：建立6個redis執行個體，連接埠號碼從7001~7006

第二步：修改redis的設定檔

1、修改連接埠號碼

2、開啟cluster-enable前面的注釋。

第三步：把建立叢集的ruby指令碼複製到redis-cluster目錄下。

第四步：啟動6個redis執行個體

第五步：建立叢集。

./redis-trib.rb create --replicas 1 192.168.25.153:7001 192.168.25.153:7002 192.168.25.153:7003 192.168.25.153:7004 192.168.25.153:7005  192.168.25.153:7006

[root@shuang redis-cluster]# ./redis-trib.rb create --replicas 1 192.168.25.153:7001 192.168.25.153:7002 192.168.25.153:7003 192.168.25.153:7004 192.168.25.153:7005  192.168.25.153:7006

>>> Creating cluster

Connecting to node 192.168.25.153:7001: OK

Connecting to node 192.168.25.153:7002: OK

Connecting to node 192.168.25.153:7003: OK

Connecting to node 192.168.25.153:7004: OK

Connecting to node 192.168.25.153:7005: OK

Connecting to node 192.168.25.153:7006: OK

>>> Performing hash slots allocation on 6 nodes...

Using 3 masters:

192.168.25.153:7001

192.168.25.153:7002

192.168.25.153:7003

Adding replica 192.168.25.153:7004 to 192.168.25.153:7001

Adding replica 192.168.25.153:7005 to 192.168.25.153:7002

Adding replica 192.168.25.153:7006 to 192.168.25.153:7003

M: 5a8523db7e12ca600dc82901ced06741b3010076 192.168.25.153:7001

   slots:0-5460 (5461 slots) master

M: bf6f0929044db485dea9b565bb51e0c917d20a53 192.168.25.153:7002

   slots:5461-10922 (5462 slots) master

M: c5e334dc4a53f655cb98fa3c3bdef8a808a693ca 192.168.25.153:7003

   slots:10923-16383 (5461 slots) master

S: 2a61b87b49e5b1c84092918fa2467dd70fec115f 192.168.25.153:7004

   replicates 5a8523db7e12ca600dc82901ced06741b3010076

S: 14848b8c813766387cfd77229bd2d1ffd6ac8d65 192.168.25.153:7005

   replicates bf6f0929044db485dea9b565bb51e0c917d20a53

S: 3192cbe437fe67bbde9062f59d5a77dabcd0d632 192.168.25.153:7006

   replicates c5e334dc4a53f655cb98fa3c3bdef8a808a693ca

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 192.168.25.153:7001)

M: 5a8523db7e12ca600dc82901ced06741b3010076 192.168.25.153:7001

   slots:0-5460 (5461 slots) master

M: bf6f0929044db485dea9b565bb51e0c917d20a53 192.168.25.153:7002

   slots:5461-10922 (5462 slots) master

M: c5e334dc4a53f655cb98fa3c3bdef8a808a693ca 192.168.25.153:7003

   slots:10923-16383 (5461 slots) master

M: 2a61b87b49e5b1c84092918fa2467dd70fec115f 192.168.25.153:7004

   slots: (0 slots) master

   replicates 5a8523db7e12ca600dc82901ced06741b3010076

M: 14848b8c813766387cfd77229bd2d1ffd6ac8d65 192.168.25.153:7005

   slots: (0 slots) master

   replicates bf6f0929044db485dea9b565bb51e0c917d20a53

M: 3192cbe437fe67bbde9062f59d5a77dabcd0d632 192.168.25.153:7006

   slots: (0 slots) master

   replicates c5e334dc4a53f655cb98fa3c3bdef8a808a693ca

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

[root@shuang redis-cluster]# 

1.4 測試叢集

[root@shuang redis-cluster]# redis01/redis-cli -h 192.168.25.153 -p 7002 -c

[root@shuang redis-cluster]# redis01/redis-cli -h 192.168.25.153 -p 7002

192.168.25.153:7002> set a 100

(error) MOVED 15495 192.168.25.153:7003

192.168.25.153:7002>

[root@shuang redis-cluster]# redis01/redis-cli -h 192.168.25.153 -p 7002 -c

192.168.25.153:7002> set a 100

-> Redirected to slot [15495] located at 192.168.25.153:7003

OK

192.168.25.153:7003> 

1.5 關閉redis

redis01/redis-cli -p 7001 shutdown

三、java使用redis--Jedis用戶端

需要把jedis的jar包添加到工程中，如果是maven需要添加jar包的座標。

單機版測試類別

public class JedisTest {@Testpublic void testJedisSingle() {//建立一個jedis的對象。Jedis jedis = new Jedis("192.168.25.153", 6379);//調用jedis對象的方法，方法名稱和redis的命令一致。jedis.set("key1", "jedis test");String string = jedis.get("key1");System.out.println(string);//關閉jedis。jedis.close();}/** * 使用串連池 */@Testpublic void testJedisPool() {//建立jedis串連池JedisPool pool = new JedisPool("192.168.25.153", 6379);//從串連池中獲得Jedis對象Jedis jedis = pool.getResource();String string = jedis.get("key1");System.out.println(string);//關閉jedis對象jedis.close();pool.close();}

叢集版測試類別

@Testpublic void testJedisCluster() {HashSet<HostAndPort> nodes = new HashSet<>();nodes.add(new HostAndPort("192.168.25.153", 7001));nodes.add(new HostAndPort("192.168.25.153", 7002));nodes.add(new HostAndPort("192.168.25.153", 7003));nodes.add(new HostAndPort("192.168.25.153", 7004));nodes.add(new HostAndPort("192.168.25.153", 7005));nodes.add(new HostAndPort("192.168.25.153", 7006));JedisCluster cluster = new JedisCluster(nodes);cluster.set("key1", "1000");String string = cluster.get("key1");System.out.println(string);cluster.close();}

1.1 jedis整合spring 單機版配置

<!-- 串連池配置 --><bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"><!-- 最大串連數 --><property name="maxTotal" value="30" /><!-- 最大空閑串連數 --><property name="maxIdle" value="10" /><!-- 每次釋放串連的最大數目 --><property name="numTestsPerEvictionRun" value="1024" /><!-- 釋放串連的掃描間隔（毫秒） --><property name="timeBetweenEvictionRunsMillis" value="30000" /><!-- 串連最小空閑時間 --><property name="minEvictableIdleTimeMillis" value="1800000" /><!-- 串連空閑多久後釋放, 當空閑時間>該值 且 空閑串連>最大空閑串連數 時直接釋放 --><property name="softMinEvictableIdleTimeMillis" value="10000" /><!-- 擷取串連時的最大等待毫秒數,小於零:阻塞不確定的時間,預設-1 --><property name="maxWaitMillis" value="1500" /><!-- 在擷取串連的時候檢查有效性, 預設false --><property name="testOnBorrow" value="true" /><!-- 在空閑時檢查有效性, 預設false --><property name="testWhileIdle" value="true" /><!-- 串連耗盡時是否阻塞, false報異常,ture阻塞直到逾時, 預設true --><property name="blockWhenExhausted" value="false" /></bean><!-- jedis用戶端單機版 --><bean id="redisClient" class="redis.clients.jedis.JedisPool"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="6379"></constructor-arg><constructor-arg name="poolConfig" ref="jedisPoolConfig"></constructor-arg></bean>

/** * 單機版測試 * <p>Title: testSpringJedisSingle</p> * <p>Description: </p> */@Testpublic void testSpringJedisSingle() {ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext-*.xml");JedisPool pool = (JedisPool) applicationContext.getBean("redisClient");Jedis jedis = pool.getResource();String string = jedis.get("key1");System.out.println(string);jedis.close();pool.close();}

叢集版配置

<bean id="redisClient" class="redis.clients.jedis.JedisCluster"><constructor-arg name="nodes"><set><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7001"></constructor-arg></bean><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7002"></constructor-arg></bean><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7003"></constructor-arg></bean><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7004"></constructor-arg></bean><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7005"></constructor-arg></bean><bean class="redis.clients.jedis.HostAndPort"><constructor-arg name="host" value="192.168.25.153"></constructor-arg><constructor-arg name="port" value="7006"></constructor-arg></bean></set></constructor-arg><constructor-arg name="poolConfig" ref="jedisPoolConfig"></constructor-arg></bean>

@Testpublic void testSpringJedisCluster() {ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext-*.xml");JedisCluster jedisCluster =  (JedisCluster) applicationContext.getBean("redisClient");String string = jedisCluster.get("key1");System.out.println(string);jedisCluster.close();}

jedis類使用redis的封裝（單機版）

public class JedisClientSingle implements JedisClient{@Autowiredprivate JedisPool jedisPool; @Overridepublic String get(String key) {Jedis jedis = jedisPool.getResource();String string = jedis.get(key);jedis.close();return string;}@Overridepublic String set(String key, String value) {Jedis jedis = jedisPool.getResource();String string = jedis.set(key, value);jedis.close();return string;}@Overridepublic String hget(String hkey, String key) {Jedis jedis = jedisPool.getResource();String string = jedis.hget(hkey, key);jedis.close();return string;}@Overridepublic long hset(String hkey, String key, String value) {Jedis jedis = jedisPool.getResource();Long result = jedis.hset(hkey, key, value);jedis.close();return result;}@Overridepublic long incr(String key) {Jedis jedis = jedisPool.getResource();Long result = jedis.incr(key);jedis.close();return result;}@Overridepublic long expire(String key, int second) {Jedis jedis = jedisPool.getResource();Long result = jedis.expire(key, second);jedis.close();return result;}@Overridepublic long ttl(String key) {Jedis jedis = jedisPool.getResource();Long result = jedis.ttl(key);jedis.close();return result;}}

jedis類使用redis的封裝（叢集版）

public class JedisClientCluster implements JedisClient {@Autowiredprivate JedisCluster jedisCluster;@Overridepublic String get(String key) {return jedisCluster.get(key);}@Overridepublic String set(String key, String value) {return jedisCluster.set(key, value);}@Overridepublic String hget(String hkey, String key) {return jedisCluster.hget(hkey, key);}@Overridepublic long hset(String hkey, String key, String value) {return jedisCluster.hset(hkey, key, value);}@Overridepublic long incr(String key) {return jedisCluster.incr(key);}@Overridepublic long expire(String key, int second) {return jedisCluster.expire(key, second);}@Overridepublic long ttl(String key) {return jedisCluster.ttl(key);}}

把緩衝添加到商務邏輯樣本，這裡可以用到切面的思想更加簡單

@Overridepublic List<TbContent> getContentList(long contentCid) {//從緩衝中取內容try {String result = jedisClient.hget(INDEX_CONTENT_REDIS_KEY, contentCid + "");if (!StringUtils.isBlank(result)) {//把字串轉換成listList<TbContent> resultList = JsonUtils.jsonToList(result, TbContent.class);return resultList;}} catch (Exception e) {e.printStackTrace();}//根據內容分類id查詢內容列表TbContentExample example = new TbContentExample();Criteria criteria = example.createCriteria();criteria.andCategoryIdEqualTo(contentCid);//執行查詢List<TbContent> list = contentMapper.selectByExample(example);//向緩衝中新增內容try {//把list轉換成字串String cacheString = JsonUtils.objectToJson(list);jedisClient.hset(INDEX_CONTENT_REDIS_KEY, contentCid + "", cacheString);} catch (Exception e) {e.printStackTrace();}return list;}