序言：多实例？Why？
随着硬件层面的发展，linux系统多核已经是普通趋势，而mysql是单进程多线程，所以先天上对多进程的利用不是很高，虽然5.6版本已经在这方面改进很多，但是也没有达到100%，所以为了充分的利用系统资源，mysql有自己的补充，那就是可以部署多实例，一个实例一个端口。
1，准备好mysql环境
1.1，准备好安装环境
groupaddmysql
useradd-g mysql mysql
autoreconf--force --install
libtoolize--automake --force
automake--force --add-missing
yuminstall -y libtoolize
yuminstall cmake -y
yuminstall gcc gcc-c++ -y
yuminstall -y ncurses-devel.x86_64
yuminstall -y cmake.x86_64
yuminstall -y libaio.x86_64
yuminstall -y bison.x86_64
yuminstall -y gcc-c++.x86_64
yuminstall make -y
1.2，创建mysql编译根目录
mkdir-p /usr/local/mysql
1.3，解压缩源码包
tar -xvf mysql-5.6.12.tar.gz
cd mysql-5.6.12
1.4，编译安装
timecmake . -DCMAKE_INSTALL_PREFIX=/usr/local/mysql-DMYSQL_DATADIR=/home/data/mysql/data -DWITH_INNOBASE_STORAGE_ENGINE=1-DMYSQL_UNIX_ADDR==/usr/local/mysql/mysql.sock -DMYSQL_USER=mysql-DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci
由于time make耗时比较长，所以事先已经安装好
timemake
timemake install
2，准备第一个实例3307
2.1建立好目录
mkdir /usr/local/mysql3307
chown -R mysql.mysql /usr/local/mysql3307/
mkdir -p /home/data/mysql3307/data
chown -R mysql.mysql /home/data/mysql3307
chown -R mysql.mysql/home/data/mysql3307/data
mkdir -p /home/data/mysql3307/binlog
chown -R mysql.mysql /home/data/mysql3307
mkdir -p /home/data/mysql3307/relay_log/
chown -R mysql.mysql /home/data/mysql3307/
2.2 配置文件
[mysqld_multi]
mysqld = /usr/local/mysql/bin/mysqld_safe
mysqladmin =/usr/local/mysql/bin/mysqladmin
log =/home/mysql/mydata/log/mysqld_multi.log
[mysqld1]
socket = /usr/local/mysql3307/mysql.sock
port = 3307
pid-file = /usr/local/mysql3307/mysqld.pid
datadir = /home/data/mysql3307/data
log_bin=/home/data/mysql3307/binlog
server-id = 1230
relay_log =/home/data/mysql3307/relay_log/mysql-relay-bin
log_slave_updates = 1
read_only = 0
innodb_buffer_pool_size = 128M
innodb_flush_log_at_trx_commit = 0
2.3 初始化数据库
/usr/local/mysql/scripts/mysql_install_db--user=mysql --basedir=/usr/local/mysql --datadir=/home/data/mysql3307/data
3，准备第二个实例3308
3.1 建立好目录
mkdir /usr/local/mysql3308
chown -R mysql.mysql /usr/local/mysql3308/
mkdir -p /home/data/mysql3308/data
chown -R mysql.mysql /home/data/mysql3308
chown -R mysql.mysql/home/data/mysql3308/data
mkdir -p /home/data/mysql3308/binlog
chown -R mysql.mysql /home/data/mysql3308
mkdir -p /home/data/mysql3308/relay_log/
chown -R mysql.mysql /home/data/mysql3308/
3.2 配置文件
[mysqld2]
socket = /usr/local/mysql3308/mysql.sock
port = 3308
pid-file = /usr/local/mysql3308/mysqld.pid
datadir = /home/data/mysql3308/data
log_bin=/home/data/mysql3308/binlog
server-id = 2230
relay_log =/home/data/mysql3308/relay_log/mysql-relay-bin
log_slave_updates = 1
read_only = 0
innodb_buffer_pool_size = 128M
innodb_flush_log_at_trx_commit = 0
3.3 初始化数据库
/usr/local/mysql/scripts/mysql_install_db--user=mysql --basedir=/usr/local/mysql --datadir=/home/data/mysql3308/data
4，准备第三个实例3309
4.1 建立好目录
mkdir /usr/local/mysql3309
chown -R mysql.mysql /usr/local/mysql3309/
mkdir -p /home/data/mysql3309/data
chown -R mysql.mysql /home/data/mysql3309
chown -R mysql.mysql/home/data/mysql3309/data
mkdir -p /home/data/mysql3309/binlog
chown -R mysql.mysql /home/data/mysql3309
mkdir -p /home/data/mysql3309/relay_log/
chown -R mysql.mysql /home/data/mysql3309/
4.2 配置文件
[mysqld3]
socket = /usr/local/mysql3309/mysql.sock
port = 3309
pid-file = /usr/local/mysql3309/mysqld.pid
datadir = /home/data/mysql3309/data
log_bin=/home/data/mysql3309/binlog
server-id = 3230
relay_log = /home/data/mysql3309/relay_log/mysql-relay-bin
log_slave_updates = 1
read_only = 0
innodb_buffer_pool_size = 128M
innodb_flush_log_at_trx_commit = 0
4.3 初始化数据库
/usr/local/mysql/scripts/mysql_install_db--user=mysql --basedir=/usr/local/mysql --datadir=/home/data/mysql3309/data
初始化信息如下所示：
[mysql@data02 ~]$ /usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/home/data/mysql3309/data
WARNING: Could not write to config file /usr/local/mysql/my-new.cnf: 权限不够
Installing MySQL system tables...2015-05-14 09:31:20 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-05-14 09:31:20 12307 [Warning] Buffered warning: Changed limits: max_open_files: 1024 (requested 5000)
2015-05-14 09:31:20 12307 [Warning] Buffered warning: Changed limits: table_cache: 431 (requested 2000)
2015-05-14 09:31:20 12307 [Note] InnoDB: The InnoDB memory heap is disabled
2015-05-14 09:31:20 12307 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-05-14 09:31:20 12307 [Note] InnoDB: Compressed tables use zlib 1.2.3
2015-05-14 09:31:20 12307 [Note] InnoDB: Using CPU crc32 instructions
2015-05-14 09:31:20 12307 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2015-05-14 09:31:20 12307 [Note] InnoDB: Completed initialization of buffer pool
2015-05-14 09:31:20 12307 [Note] InnoDB: The first specified data file ./ibdata1 did not exist: a new database to be created!
2015-05-14 09:31:20 12307 [Note] InnoDB: Setting file ./ibdata1 size to 12 MB
2015-05-14 09:31:20 12307 [Note] InnoDB: Database physically writes the file full: wait...
2015-05-14 09:31:20 12307 [Note] InnoDB: Setting log file ./ib_logfile101 size to 48 MB
2015-05-14 09:31:20 12307 [Note] InnoDB: Setting log file ./ib_logfile1 size to 48 MB
2015-05-14 09:31:21 12307 [Note] InnoDB: Renaming log file ./ib_logfile101 to ./ib_logfile0
2015-05-14 09:31:21 12307 [Warning] InnoDB: New log files created, LSN=45781
2015-05-14 09:31:21 12307 [Note] InnoDB: Doublewrite buffer not found: creating new
2015-05-14 09:31:21 12307 [Note] InnoDB: Doublewrite buffer created
2015-05-14 09:31:21 12307 [Note] InnoDB: 128 rollback segment(s) are active.
2015-05-14 09:31:21 12307 [Warning] InnoDB: Creating foreign key constraint system tables.
2015-05-14 09:31:21 12307 [Note] InnoDB: Foreign key constraint system tables created
2015-05-14 09:31:21 12307 [Note] InnoDB: Creating tablespace and datafile system tables.
2015-05-14 09:31:21 12307 [Note] InnoDB: Tablespace and datafile system tables created.
2015-05-14 09:31:21 12307 [Note] InnoDB: Waiting for purge to start
2015-05-14 09:31:21 12307 [Note] InnoDB: 5.6.12 started; log sequence number 0
2015-05-14 09:31:21 12307 [Note] Binlog end
2015-05-14 09:31:21 12307 [Note] InnoDB: FTS optimize thread exiting.
2015-05-14 09:31:21 12307 [Note] InnoDB: Starting shutdown...
2015-05-14 09:31:22 12307 [Note] InnoDB: Shutdown completed; log sequence number 1625977
OK
Filling help tables...2015-05-14 09:31:22 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-05-14 09:31:22 12332 [Warning] Buffered warning: Changed limits: max_open_files: 1024 (requested 5000)
2015-05-14 09:31:22 12332 [Warning] Buffered warning: Changed limits: table_cache: 431 (requested 2000)
2015-05-14 09:31:22 12332 [Note] InnoDB: The InnoDB memory heap is disabled
2015-05-14 09:31:22 12332 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-05-14 09:31:22 12332 [Note] InnoDB: Compressed tables use zlib 1.2.3
2015-05-14 09:31:22 12332 [Note] InnoDB: Using CPU crc32 instructions
2015-05-14 09:31:22 12332 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2015-05-14 09:31:22 12332 [Note] InnoDB: Completed initialization of buffer pool
2015-05-14 09:31:22 12332 [Note] InnoDB: Highest supported file format is Barracuda.
2015-05-14 09:31:22 12332 [Note] InnoDB: 128 rollback segment(s) are active.
2015-05-14 09:31:22 12332 [Note] InnoDB: Waiting for purge to start
2015-05-14 09:31:22 12332 [Note] InnoDB: 5.6.12 started; log sequence number 1625977
2015-05-14 09:31:22 12332 [Note] Binlog end
2015-05-14 09:31:22 12332 [Note] InnoDB: FTS optimize thread exiting.
2015-05-14 09:31:22 12332 [Note] InnoDB: Starting shutdown...
2015-05-14 09:31:24 12332 [Note] InnoDB: Shutdown completed; log sequence number 1625987
OK
To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/usr/local/mysql/bin/mysqladmin -u root password 'new-password'
/usr/local/mysql/bin/mysqladmin -u root -h data02 password 'new-password'
Alternatively you can run:
/usr/local/mysql/bin/mysql_secure_installation
which will also give you the option of removing the test
databases and anonymous user created by default. This is
strongly recommended for production servers.
See the manual for more instructions.
You can start the MySQL daemon with:
cd . ; /usr/local/mysql/bin/mysqld_safe &
You can test the MySQL daemon with mysql-test-run.pl
cd mysql-test ; perl mysql-test-run.pl
Please report any problems with the ./bin/mysqlbug script!
The latest information about MySQL is available on the web at
http://www.mysql.com
Support MySQL by buying support/licenses at http://shop.mysql.com
WARNING: Could not copy config file template /usr/local/mysql/support-files/my-default.cnf to
/usr/local/mysql/my-new.cnf, may not have access rights to do so.
You may want to copy the file manually, or create your own,
it will then be used by default by the server when you start it.
WARNING: Default config file /etc/my.cnf exists on the system
This file will be read by default by the MySQL server
If you do not want to use this, either remove it, or use the
--defaults-file argument to mysqld_safe when starting the server
5，启动多实例数据库
mkdir -p /home/mysql/data/log
[mysql@data02 data]$ mysqld_multi--defaults-extra-file=/etc/my.cnf start 1,2,3
[mysql@data02 data]$
后台日志信息：
Starting MySQL servers
150514 09:36:14 mysqld_safe Logging to'/home/data/mysql3309/data/data02.err'.
150514 09:36:15 mysqld_safe Logging to '/home/data/mysql3308/data/data02.err'.
150514 09:36:15 mysqld_safe Logging to'/home/data/mysql3307/data/data02.err'.
150514 09:36:15 mysqld_safe Starting mysqlddaemon with databases from /home/data/mysql3308/data
150514 09:36:15 mysqld_safe Starting mysqlddaemon with databases from /home/data/mysql3307/data
150514 09:36:15 mysqld_safe Starting mysqlddaemon with databases from /home/data/mysql3309/data
6，查看多实例
[mysql@data02 ~]$ mysqld_multi--defaults-extra-file=/etc/my.cnf report
Reporting MySQL servers
MySQL server from group: mysqld1 is running
MySQL server from group: mysqld2 is running
MySQL server from group: mysqld3 is running
[mysql@data02 ~]$
后台日志信息：
Reporting MySQL servers
MySQL server from group: mysqld1 is running
MySQL server from group: mysqld2 is running
MySQL server from group: mysqld3 is running
7，停止多实例
mysqld_multi--defaults-extra-file=/etc/my.cnf stop 1,2,3
后台日志信息：
Stopping MySQL servers
150514 09:35:43 mysqld_safe mysqld from pidfile /usr/local/mysql3309/mysqld.pid ended
150514 09:35:43 mysqld_safe mysqld from pidfile /usr/local/mysql3307/mysqld.pid ended
150514 09:35:43 mysqld_safe mysqld from pidfile /usr/local/mysql3308/mysqld.pid ended
8，各自登录mysql实例
需要指定启动的socket就可以登录到各自的mysql实例，如下所示：
[mysql@data02 ~]$ mysql --socket=/usr/local/mysql3308/mysql.sock
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.6.12-log Sourcedistribution
Copyright (c) 2000, 2013, Oracle and/or itsaffiliates. All rights reserved.
Oracle is a registered trademark of OracleCorporation and/or its
affiliates. Other names may be trademarksof their respective
owners.
Type 'help;' or '\h' for help. Type '\c' toclear the current input statement.
mysql> select @@port;
+--------+
| @@port |
+--------+
| 3308 |
+--------+
1 row in set (0.00 sec)
mysql>
mysql> create database d3308;
Query OK, 1 row affected (0.04 sec)
mysql>
9，可以在多端口上搭建主从、主主服务
9.1，在3307实例建立账号
复制账号
GRANTREPLICATION SLAVE,RELOAD,SUPER ON *.*TO repl@'192.168.52.%' IDENTIFIED BY'repl_1234';
备份账号
GRANTRELOAD, SUPER, LOCK TABLES, REPLICATION CLIENT, CREATE TABLESPACE ON *.* TO'backup'@'192.168.%' IDENTIFIED BY '123456';
GRANTALL PRIVILEGES ON `mysql`.* TO 'backup'@'192.168.%';
GRANTEVENT ON *.* TO 'backup'@'192.168.%';
9.2，将数据从3307实例同步到3308端口
备份：
/usr/local/mysql/bin/mysqldump-ubackup --password=123456 --host=192.168.52.138--socket=/usr/local/mysql3307/mysql.sock --port=3307 -R -E --skip-opt--single-transaction --flush-logs --master-data=2 --add-drop-table--create-option --quick --extended-insert=false --set-charset --disable-keys-A > /tmp/alldbfullbackup.sql
导入：
/usr/local/mysql/bin/mysql-uroot -p --socket=/usr/local/mysql3308/mysql.sock --port=3308</tmp/alldbfullbackup.sql
9.3，在3308实例上建立复制链接
找到复制点
more/tmp/alldbfullbackup.sql
开始建立复制链接
CHANGE MASTER TOMASTER_HOST='192.168.52.138',MASTER_PORT=3307,
MASTER_USER='repl',
MASTER_PASSWORD='repl_1234',
MASTER_LOG_FILE='mysql-bin.000006',
MASTER_LOG_POS=120;
开启复制
startslave;
查看复制状态
showslave status\G;
mysql> show slave status\G
*************************** 1. row***************************
Slave_IO_State: Waiting formaster to send event
Master_Host: 192.168.52.138
Master_User: repl
Master_Port: 3307
Connect_Retry: 60
Master_Log_File: mysql-bin.000011
Read_Master_Log_Pos: 120
Relay_Log_File:mysql-relay-bin.000005
Relay_Log_Pos: 283
Relay_Master_Log_File: mysql-bin.000011
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
……
Seconds_Behind_Master: 0
10，管理单个实例
停止实例2：
[root@data03 ~]# mysqld_multi--defaults-extra-file=/etc/my.cnf stop 2
[root@data03 ~]#
后台日志信息：
Stopping MySQL servers
150517 06:53:43 mysqld_safe mysqld from pidfile /usr/local/mysql3308/mysqld.pid ended
mysqld_multi log file version 2.16; run: 日 5月 17 06:53:48 2015
启动实例2：
[root@data03 ~]# mysqld_multi--defaults-extra-file=/etc/my.cnf start 2
[root@data03 ~]#
后台日志信息：
Starting MySQL servers
150517 06:53:48 mysqld_safe Logging to'/home/data/mysql3308/data/data03.err'.
150517 06:53:48 mysqld_safe Starting mysqlddaemon with databases from /home/data/mysql3308/data
11，如何使用多实例
由于多实例中，各个实例的资源都是不share的，所以要合理分配好各个实例的内存、磁盘等资源，避免out of memery或则 full disk的情况出现。
