Redis

Posted 2020-08-02

Redis

redis 是一个高性能的 key-value 数据库。 redis 的出现，很大程度补偿了memcached 这类 keyvalue 存储的不足，在部分场合可以对关系数据库起到很好的补充作用。它提供了 Python，Ruby，Erlang，php 客户端，使用方便。Redis 的所有数据都是保存在内存中，然后不定期的通过异步方式保存到磁盘上(这称为“半持久化模式”)；也可以把每一次数据变化都写入到一个 append only file(aof)里面(这称为“全持久化模式”)。

Redis 由四个可执行文件：redis-benchmark、redis-cli、redis-server、redis-stat 这四个文件，加上一个redis.conf就构成了整个redis的最终可用包。它们的作用如下：

redis-server：Redis服务器的daemon启动程序

redis-cli：Redis命令行操作工具。当然，你也可以用telnet根据其纯文本协议来操作

redis-benchmark：Redis性能测试工具，测试Redis在你的系统及你的配置下的读写性能

redis-stat：Redis状态检测工具，可以检测Redis当前状态参数及延迟状况

1.安装并配置Redis

tar zxf redis-3.0.2.tar.gz

cd redis-3.0.2

yum install -y gcc

make

make install

cd utils/

./install_server.sh  ##启动脚本

/etc/init.d/redis_6379 restart  ##启动Redis

 

2.安装Redis的Php扩展

yum install nginx-1.8.0-1.el6.ngx.x86_64.rpm php-* -y

unzip phpredis-master.zip

vim /etc/php.ini

date.timezone = Asia/Shanghai  ##将时区改成亚洲/上海

/etc/init.d/php-fpm restart  ##重启Php

vim /etc/php-fpm.d/www.conf

; RPM: apache Choosed to be able to access some dir as httpd

user = nginx  ##将php-fpm的用户改为nginx

; RPM: Keep a group allowed to write in log dir.

group = nginx  ##将php-fpm的用户组改为nginx

cd phpredis-master/

phpize

./configure  ##编译

make  && make install  ##安装

cd  /etc/php.d/

cp mysql.ini redis.ini

vim redis.ini

extension=redis.so

/etc/init.d/php-fpm restart  ##重启php

 

3.配置Nginx

# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000

    location ~ \.php$ {

        root           html;

        fastcgi_pass   127.0.0.1:9000;

        fastcgi_index  index.php;

        fastcgi_param  SCRIPT_FILENAME  /usr/share/nginx/html$fastcgi_script_name;

        include        fastcgi_params;

    }

/etc/init.d/nginx restart  ##重启Nginx

 

4.配置Mysql并测试

/etc/init.d/mysqld start  ##启动数据库

mysql

mysql> grant all on *.* to [email protected] identified by ‘westos‘;

Query OK, 0 rows affected (0.00 sec)

mysql> quit

Bye

cd redis/

mysql < test.sql  ##将测试数据库导入Mysql

mysql

mysql> use test;

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

 

Database changed

mysql> select * from test;

+----+-------+

| id | name  |

+----+-------+

|  1 | test1 |

|  2 | test2 |

|  3 | test3 |

|  4 | test4 |

|  5 | test5 |

|  6 | test6 |

|  7 | test7 |

|  8 | test8 |

|  9 | test9 |

+----+-------+

9 rows in set (0.00 sec)

登陆172.25.35.6测试，如图：

 

 

我们实现了redis作为mysql的缓存服务器,但是如果更新了mysql,redis中仍然会有对应的 KEY,数据就不会更新,此时就会出现mysql和redis数据不一致的情况。所以接下来就要通过 mysql 触发器将改变的数据同步到redis中。

我们可以通过Gearman来实现数据同步：

Gearman 是一个支持分布式的任务分发框架:

Gearman Job Server:Gearman 核心程序,需要编译安装并以守护进程形式运行在后台。

Gearman Client:可以理解为任务的请求者。

Gearman Worker:任务的真正执行者,一般需要自己编写具体逻辑并通过守护进程方式

运行,Gearman Worker 接收到 Gearman Client 传递的任务内容后,会按顺序处理。

 

5.安装并且配置Gearman

cd redis/

yum install gcc libgearman-devel-1.1.8-2.el6.x86_64.rpm

libevent-devel-1.4.13-4.el6.x86_64.rpm  

libevent-doc-1.4.13-4.el6.noarch.rpm

libevent-headers-1.4.13-4.el6.noarch.rpm

libgearman-1.1.8-2.el6.x86_64.rpm

tokyocabinet-1.4.33-6.el6.x86_64.rpm

cd gearman-1.1.2/

./configure

make && make install

 

6.安装lib_mysqludf_json

lib_mysqludf_json UDF 库函数将关系数据映射为 JSON 格式。通常,数据库中的数据映射为 JSON 格式,是通过程序来转换的。

unzip lib_mysqludf_json-master.zip

cd lib_mysqludf_json-master/

gcc $(mysql_config --cflags) -shared -fPIC -o lib_mysqludf_json.so lib_mysqludf_json.c

mysql

mysql> show global variables like ‘plugin_dir‘;

+---------------+-------------------------+

| Variable_name | Value                   |

+---------------+-------------------------+

| plugin_dir    | /usr/lib64/mysql/plugin |

+---------------+-------------------------+

1 row in set (0.00 sec)

cp lib_mysqludf_json.so /usr/lib64/mysql/plugin/  ##拷贝lib_mysqludf_json.so模块

mysql> create function json_object returns string soname

->  ‘lib_mysqludf_json.so‘;  ##注册UDF函数

 

7.安装gearman-mysql-udf来管理调用gearman

tar zxf gearman-mysql-udf-0.6.tar.gz

cd gearman-mysql-udf-0.6/

yum install -y gcc-c++

./configure --libdir=/usr/lib64/mysql/plugin/

make && make install

mysql

mysql> create function gman_do_background returns string soname  ‘lib_mysqludf_json.so‘;

##注册UDF函数

mysql> create function gman_servers_set returns string soname  ‘lib_mysqludf_json.so‘;

mysql> select * from mysql.func;

+--------------------+-----+-------------------------+----------+

| name               | ret | dl                      | type     |

+--------------------+-----+-------------------------+----------+

| json_object        |   0 | lib_mysqludf_json.so    | function |

| gman_do_background |   0 | libgearman_mysql_udf.so | function |

| gman_servers_set   |   0 | libgearman_mysql_udf.so | function |

+--------------------+-----+-------------------------+----------+

3 rows in set (0.00 sec)  ##查看注册的函数

mysql> select gman_servers_set(‘127.0.0.1:4730‘);  ##指定Gearman的服务信息

+------------------------------------+

| gman_servers_set(‘127.0.0.1:4730‘) |

+------------------------------------+

| 127.0.0.1:4730                     |

+------------------------------------+

1 row in set (0.00 sec)

mysql> quit

Bye

vim /root/redis/test.sql

use test;

#CREATE TABLE `test` (`id` int(7) NOT NULL AUTO_INCREMENT, `name` char(8)

DEFAULT NULL, PRIMARY KEY (`id`)) ENGINE=InnoDB DEFAULT CHARSET=utf8;

#INSERT INTO `test` VALUES (1,‘test1‘),(2,‘test2‘),(3,‘test3‘),(4,‘test4‘),(5,‘test5‘),(6,‘test6‘),(7,‘test7‘),(8,‘test8‘),(9,‘test9‘);

 

DELIMITER $$  ##编写Mysql的触发器

CREATE TRIGGER datatoredis AFTER UPDATE ON test FOR EACH ROW BEGIN

    SET @RECV=gman_do_background(‘syncToRedis‘, json_object(NEW.id as `id`, NEW.name as `name`));

  END$$

DELIMITER ;

mysql < test.sql  ##将检测数据库导入mysql

mysql

mysql> SHOW TRIGGERS FROM test;  ##查看触发器

+-------------+--------+-------+----------------------------------------------------------------------------------------------------------------+--------+---------+----------+----------------+----------------------+----------------------+--------------------+

| Trigger     | Event  | Table | Statement                                                                                                      | Timing | Created | sql_mode | Definer        | character_set_client | collation_connection | Database Collation |

+-------------+--------+-------+----------------------------------------------------------------------------------------------------------------+--------+---------+----------+----------------+----------------------+----------------------+--------------------+

| datatoredis | UPDATE | test  | BEGIN

    SET @RECV=gman_do_background(‘syncToRedis‘, json_object(NEW.id as `id`, NEW.name as `name`));

  END | AFTER  | NULL    |          | [email protected] | latin1               | latin1_swedish_ci    | latin1_swedish_ci  |

+-------------+--------+-------+----------------------------------------------------------------------------------------------------------------+--------+---------+----------+----------------+----------------------+----------------------+--------------------+

1 row in set (0.00 sec)

 

8.配置Gearman的worker端

cp worker.php /usr/local/bin/

cd /usr/local/bin/

nohup php worker.php &

[1] 9068  ##将worker打入后台运行

vim worker.php

<?php

$worker = new GearmanWorker();

$worker->addServer();

$worker->addFunction(‘syncToRedis‘, ‘syncToRedis‘);

 

$redis = new Redis();

$redis->connect(‘127.0.0.1‘, 6379);

 

while($worker->work());

function syncToRedis($job)

{

        global $redis;

        $workString = $job->workload();

        $work = json_decode($workString);

        if(!isset($work->id)){

                return false;

        }

        $redis->set($work->id, $work->name);

}

?>

 

9.更新Mysql中的数据并检测

mysql

mysql> use test;

mysql> update test set name=‘hello‘ where id=1;

Query OK, 1 row affected (0.12 sec)

mysql> update test set name=‘world‘ where id=2;

Query OK, 1 row affected (0.06 sec)

mysql> select * from test;

+----+-------+

| id | name  |

+----+-------+

|  1 | hello |

|  2 | world |

|  3 | test3 |

|  4 | test4 |

|  5 | test5 |

|  6 | test6 |

|  7 | test7 |

|  8 | test8 |

|  9 | test9 |

+----+-------+

9 rows in set (0.00 sec)

mysql> quit

Bye

如图：

 

 

10.主从复制

master:172.25.35.6

slave:172.25.35.7

     172.25.35.8

在slave端：

vim /etc/redis/6379.conf

slaveof 172.25.35.6 6379

 

测试：

[[email protected] bin]# redis-cli

127.0.0.1:6379> set 1 westos

OK

127.0.0.1:6379> get 1

"westos"

[[email protected] redis-3.0.2]# redis-cli

127.0.0.1:6379> get 1

"westos"

[[email protected] ~]# redis-cli

127.0.0.1:6379> get 1

"westos"

本文出自 “jeffrey13” 博客，谢绝转载！