heartbeat实现MySQL双机高可用
对于一个网站或一个企业最重要的无疑就是数据,那么数据库的数据安全无疑就更加重要,所以我们必须保证数据库的数据完整,这里就介绍使用heartbeat来实现MySQL双机高可用. 当我们的MySQL数据库故障或MySQL数据库服务器出现故障的时候我们希望有一个备用能自动代
对于一个网站或一个企业最重要的无疑就是数据,那么数据库的数据安全无疑就更加重要,所以我们必须保证数据库的数据完整,这里就介绍使用heartbeat来实现MySQL双机高可用.
当我们的MySQL数据库故障或MySQL数据库服务器出现故障的时候我们希望有一个备用能自动代替主MySQL数据来完成当前的任务,当主MySQL服务器恢复故障的时候备用的能切换到备用等待下一次故障出现.这里我们就结合故障检测HA来实现.
HA会定时发送心跳包检测主备服务器的健康状态,当主服务器出现故障时会自动将vip切换到备用服务器,由备用服务器执行主服务器的任务,MySQL要实现这样的功能就必须保证主备服务器的数据一致.这就要用到MySQL主从双机. 本文使用环境: 系统:CentOS 5.5 32位 主MySQL: ip 192.168.3.101/24 主机名:master.org 备用MySQL:192.168.3.102/24???主机名:slave.org vip:192.168.3.103/24 MySQL:mysql-5.0.95.tar.gz heartbeat:Heartbeat-3-0-7e3a82377fa8.tar.bz2
一、安装部署MySQL
yum -y install ncurses-devel openssl-devel wget http://dev.mysql.com/get/Downloads/MySQL-5.0/mysql-5.0.95.tar.gz/from/http://mysql.cdpa.nsysu.edu.tw/ useradd -M -s /sbin/nologin mysql tar -zxvf mysql-5.0.95.tar.gz cd mysql-5.0.95 ./configure --prefix=/usr/local/mysql \ --without-debug \ --with-extra-charsets=utf8,gbk \ --enable-assembler \ --with-mysqld-ldflags=-all-static \ --with-client-ldflags=-all-static \ --with-unix-socket-path=/tmp/mysql.sock \ --with-ssl make && make install cp support-files/my-medium.cnf /etc/my.cnf # 创建配置文件 cp support-files/mysql.server /etc/init.d/mysqld # 创建启动脚本 chmod +x /etc/init.d/mysqld echo '/usr/local/mysql/lib/mysql/' >> /etc/ld.so.conf ldconfig /usr/local/mysql/bin/mysql_install_db --user=mysql # 初始化数据库 chown -R root.mysql /usr/local/mysql/ chown -R mysql.mysql /usr/local/mysql/var/ ln -s /usr/local/mysql/bin/* /usr/local/bin/ # 为二进制文件做一个软链接
配置MySQl主从实现数据同步,在主从服务器上修改my.cnf(这里是新安装的数据库,如果是仅仅加从库,需要把主库的数据备份导入到从库,这里不再讲述)
vi /etc/my.cnf # [mysqld]里修改: log_bin = /var/log/mysql/mysql-bin.log # 启动二进制文件 server-id = 1921683101 # 设置服务器id
启动主库:
service mysqld start
在主库上创建一个用户授权给从库,用户为backup密码为backup:
mysql> grant replication slave on *.* to 'backup'@'192.168.3.102' identified by 'backup'; Query OK, 0 rows affected (0.16 sec)
查看主库状态:
mysql> show master status; +------------------+-----------+--------------+------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+-----------+--------------+------------------+ | mysql-bin.000003 | 236 | | | +------------------+-----------+--------------+------------------+ 1 row in set (0.00 sec)
修改从库配置文件:
server-id = 1921683102 # server id必须保持唯一 log_bin = /var/log/mysql/mysql-bin.log # 启用二进制日志 master-host = 192.168.3.101 # 主库ip master-user = backup # 账号 master-pass = backup # 密码 master-port = 3306 # 连接主库的端口 master-connect-retry=60 # 连接失败后进行重试等待的描述
启动从库,并查看状态:
service mysqld start
在从库上执行下操作,指定主库的二进制文件名和偏移量(刚才在主库show master status;查看的参数):
mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.3.101
Master_User: backup
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000003
Read_Master_Log_Pos: 236
Relay_Log_File: cfhost-relay-bin.000002
Relay_Log_Pos: 235
Relay_Master_Log_File: mysql-bin.000003
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 236
Relay_Log_Space: 235
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
1 row in set (0.00 sec)
ERROR:
No query specified
如果show slave status \G;Slave_SQL_Running: No,则执在从库上执行下面命令(两个参数值通过在主库执行show master status; 命令查看获得):
mysql> stop slave; Query OK, 0 rows affected (0.00 sec) mysql> change master to master_log_file='mysql-bin.000003',master_log_pos=236; Query OK, 0 rows affected (0.01 sec)
在主库上创建一个数据库看看是否同步.
二、安装部署heartbeat实现双机热备份
安装依赖
yum -y install pkgconfig glib2-devel python-devel pam-devel gnutls-devel swig
安装libnet
wget http://download.fedora.redhat.com/pub/epel/5/i386/libnet-1.1.5-1.el5.i386.rpm rpm -ivh libnet-1.1.5-1.el5.i386.rpm wget http://download.fedora.redhat.com/pub/epel/5/i386/libnet-devel-1.1.5-1.el5.i386.rpm rpm -ivh libnet-devel-1.1.5-1.el5.i386.rpm
安装:
useradd -M -s /sbin/nologin hacluster useradd -M -s /sbin/nologin haclient wget http://www.ultramonkey.org/download/heartbeat/2.0.8/heartbeat-2.0.8.tar.gz tar -zxvf heartbeat-2.0.8.tar.gz cd heartbeat-2.0.8 ./configure --sysconfdir=/etc make && make install
创建配置文件: 安装后要配置三个文件（如没有可手动建立）：ha.cf、haresources、authkeys。这三个配置文件需要在/etc/ha.d目录下面，但是默认是没有这三个文件的，可以到官网上下这三个文件，也可以在源码包里找这三个文件，在源码目录下的DOC子目录里。
cat /usr/local/share/doc/heartbeat-2.0.8/ha.cf | egrep -v '^#\W' | grep -v '^#$' >> /etc/ha.d/ha.cf cat /usr/local/share/doc/heartbeat-2.0.8/haresources? | egrep -v '^#\W' | grep -v '^#$' >> /etc/ha.d/haresources cat /usr/local/share/doc/heartbeat-2.0.8/authkeys | egrep -v '^#\W' | grep '^#$' -v > /etc/ha.d/authkeys
编辑配置文件:
编辑ha.cf,该文件中包括为Heartbeat使用何种介质通路和如何配置他们的信息.
vi /etc/ha.d/ha.cf debugfile /var/log/ha-debug # 用于记录heartbeat的调试信息 logfile /var/log/ha-log # 用于记录heartbeat的日志信息 logfacility local0 keepalive 2 # 设置心跳间隔 watchdog /dev/watchdog deadtime 30 # 在30秒后宣布节点死亡 warntime 10 # 在日志中发出“late heartbeat“警告之前等待的时间，单位为秒 initdead 120 # 网络启动时间 udpport 694 # 广播/单播通讯使用的udp端口 #baud 19200 #serial /dev/ttyS0 # 使用串口heartbeat bcast eth0 # 使用网卡heartbeat,并在eth0接口上使用广播heartbeat auto_failback on # 当主节点从故障中恢复时,将自动切换到主节点 watchdog /dev/watchdog # 该指令是用于设置看门狗定时器，如果节点一分钟内都没有心跳，那么节点将重新启动 node master.org # 集群中机器的主机名，与“uname –n”的输出相同。 node slave.org ping 192.168.3.254 # ping网关来检测链路正常 respawn hacluster /usr/local/lib/heartbeat/ipfail # respawn调用/usr/lib/heartbeat/ipfail来主动进行切换 apiauth ipfail gid=haclient uid=hacluster # 设置启动ipfail的用户和组
配置haresources ,该文件列出所有节点所提供的服务以及服务的默认所有者.所有节点上的该文件必须相同
vi /etc/ha.d/haresources master.org IPaddr::192.168.3.103 mysql # vip
注意:!!haresources最后一个字段是某个服务的心跳,如果mysql,如果主从库使用的是同一台盘阵或者一个分布式文件系统,这里一定要填写真实的启动脚本(/etc/init.d下),如果是主从同步的话请务必不填写真正的启动脚本,因为主库心跳存活的话heartbeat会自动停止从库的mysql,这样就无法同步,主库发生故障时转移故障就没有意义.
配置authkeys,?authkeys决定了您的认证密钥。共有三种认证方式：crc，md5，和sha1果您的Heartbeat运行于 安全 网络之上，如本例中的交叉线，可以使用crc，从资源的角度来看，这是代价最低的方法。如果网络并不 安全 ，但您也希望降低CPU使用，则使用md5。最后，如果您想得到最好的认证，而不考虑CPU使用情况，则使用sha1，它在三者之中最难破解。
vi /etc/ha.d/authkeys auth 1 1 crc chmod 600 /etc/ha.d/authkeys
不论您在关键字auth后面指定的是什么索引值，在后面必须要作为键值再次出现。如果您指定“auth 4”，则在后面一定要有一行的内容为“4 ”。 配置从库:
scp root@192.168.3.101:/etc/ha.d/ha.cf /etc/ha.d/ scp root@192.168.3.101:/etc/ha.d/authkeys /etc/ha.d/ scp root@192.168.3.101:/etc/ha.d/haresources /etc/ha.d/ vi /etc/ha.d/ha.cf debugfile /var/log/ha-debug logfile /var/log/ha-log logfacility???? local0 keepalive 2 deadtime 30 warntime 10 initdead 120 udpport 694 bcast?? eth0?????????? auto_failback on node??? master.org node??? slave.org ping 192.168.3.254 respawn hacluser /usr/local/lib/heartbeat/ipfail # respawn调用/usr/lib/heartbeat/ipfail来主动进行切换 apiauth ipfail gid=haclient uid=hacluster
启动主库heartbeat:
server heartbeat start
查看日志:
cat /var/log/ha-log heartbeat[32239]: 2012/02/19_13:45:29 info: Link 192.168.3.254:192.168.3.254 up. heartbeat[32239]: 2012/02/19_13:45:29 info: Status update for node 192.168.3.254: status ping heartbeat[32239]: 2012/02/19_13:45:29 info: Link master.org:eth0 up. heartbeat[32239]: 2012/02/19_13:45:41 WARN: node slave.org: is dead heartbeat[32239]: 2012/02/19_13:45:41 info: Comm_now_up(): updating status to active heartbeat[32239]: 2012/02/19_13:45:41 info: Local status now set to: 'active' heartbeat[32239]: 2012/02/19_13:45:41 info: Starting child client "/usr/local/lib/heartbeat/ipfail" (503,503) heartbeat[32239]: 2012/02/19_13:45:41 WARN: No STONITH device configured. heartbeat[32239]: 2012/02/19_13:45:41 WARN: Shared disks are not protected. heartbeat[32239]: 2012/02/19_13:45:41 info: Resources being acquired from slave.org. heartbeat[32247]: 2012/02/19_13:45:41 info: Starting "/usr/local/lib/heartbeat/ipfail" as uid 503 gid 503 (pid 32247) harc[32248]: 2012/02/19_13:45:42 info: Running /etc/ha.d/rc.d/status status mach_down[32275]: 2012/02/19_13:45:42 info: /usr/local/lib/heartbeat/mach_down: nice_failback: foreign resources acquired mach_down[32275]: 2012/02/19_13:45:42 info: mach_down takeover complete for node slave.org. heartbeat[32239]: 2012/02/19_13:45:42 info: mach_down takeover complete. heartbeat[32239]: 2012/02/19_13:45:42 info: Initial resource acquisition complete (mach_down) IPaddr[32300]: 2012/02/19_13:45:42 INFO: Resource is stopped heartbeat[32249]: 2012/02/19_13:45:42 info: Local Resource acquisition completed. harc[32338]: 2012/02/19_13:45:42 info: Running /etc/ha.d/rc.d/ip-request-resp ip-request-resp ip-request-resp[32338]: 2012/02/19_13:45:42 received ip-request-resp IPaddr::192.168.3.103 OK yes ResourceManager[32353]: 2012/02/19_13:45:42 info: Acquiring resource group: master.org IPaddr::192.168.3.103 mysqld IPaddr[32377]: 2012/02/19_13:45:42 INFO: Resource is stopped ResourceManager[32353]: 2012/02/19_13:45:42 info: Running /etc/ha.d/resource.d/IPaddr 192.168.3.103 start IPaddr[32429]: 2012/02/19_13:45:42 INFO: Using calculated nic for 192.168.3.103: eth0 IPaddr[32429]: 2012/02/19_13:45:42 DEBUG: Using calculated netmask for 192.168.3.103: 255.255.255.0 IPaddr[32429]: 2012/02/19_13:45:42 DEBUG: Using calculated broadcast for 192.168.3.103: 192.168.3.255 IPaddr[32429]: 2012/02/19_13:45:42 INFO: eval /sbin/ifconfig eth0:0 192.168.3.103 netmask 255.255.255.0 broadcast 192.168.3.255 IPaddr[32429]: 2012/02/19_13:45:43 DEBUG: Sending Gratuitous Arp for 192.168.3.103 on eth0:0 [eth0] IPaddr[32420]: 2012/02/19_13:45:43 INFO: Success ResourceManager[32353]: 2012/02/19_13:45:43 info: Running /etc/init.d/mysqld start heartbeat[32239]: 2012/02/19_13:45:56 info: Local Resource acquisition completed. (none) heartbeat[32239]: 2012/02/19_13:45:56 info: local resource transition completed.
从日志中看出来slave.org没起来是死亡的,并添加192.168.3.103vip
启动从库heartbeat
server heartbeat start
启动之后查看日志信息
Feb 19 13:50:22 slave heartbeat: [29159]: info: Local status now set to: 'up' Feb 19 13:50:23 slave heartbeat: [29159]: info: Link master.org:eth0 up. Feb 19 13:50:23 slave heartbeat: [29159]: info: Status update for node master.org: status active Feb 19 13:50:23 slave heartbeat: [29159]: info: Link 192.168.3.254:192.168.3.254 up. Feb 19 13:50:23 slave heartbeat: [29159]: info: Status update for node 192.168.3.254: status ping Feb 19 13:50:23 slave heartbeat: [29159]: info: Link slave.org:eth0 up. Feb 19 13:50:23 slave harc[29171]: info: Running /etc/ha.d/rc.d/status status Feb 19 13:50:24 slave heartbeat: [29159]: info: Comm_now_up(): updating status to active Feb 19 13:50:24 slave heartbeat: [29159]: info: Local status now set to: 'active' Feb 19 13:50:24 slave heartbeat: [29159]: info: Starting child client "/usr/local/lib/heartbeat/ipfail" (501,501) Feb 19 13:50:24 slave heartbeat: [29159]: WARN: G_CH_dispatch_int: Dispatch function for read child took too long to execute: 140 ms (> 50 ms) (GSource: 0x9b98448) Feb 19 13:50:24 slave heartbeat: [29182]: info: Starting "/usr/local/lib/heartbeat/ipfail" as uid 501 gid 501 (pid 29182) Feb 19 13:50:24 slave heartbeat: [29159]: info: remote resource transition completed. Feb 19 13:50:24 slave heartbeat: [29159]: info: remote resource transition completed. Feb 19 13:50:24 slave heartbeat: [29159]: info: Local Resource acquisition completed. (none) Feb 19 13:50:25 slave heartbeat: [29159]: info: master.org wants to go standby [foreign] Feb 19 13:50:26 slave heartbeat: [29159]: info: standby: acquire [foreign] resources from master.org Feb 19 13:50:26 slave heartbeat: [29183]: info: acquire local HA resources (standby). Feb 19 13:50:26 slave heartbeat: [29183]: info: local HA resource acquisition completed (standby). Feb 19 13:50:26 slave heartbeat: [29159]: info: Standby resource acquisition done [foreign]. Feb 19 13:50:26 slave heartbeat: [29159]: info: Initial resource acquisition complete (auto_failback) Feb 19 13:50:27 slave heartbeat: [29159]: info: remote resource transition completed. Feb 19 13:50:36 slave ipfail: [29182]: info: Ping node count is balanced. Feb 19 13:50:37 slave ipfail: [29182]: info: Giving up foreign resources (auto_failback). Feb 19 13:50:37 slave ipfail: [29182]: info: Delayed giveup in 4 seconds. Feb 19 13:50:42 slave ipfail: [29182]: info: giveup() called (timeout worked) Feb 19 13:50:42 slave heartbeat: [29159]: info: slave.org wants to go standby [foreign] Feb 19 13:50:43 slave heartbeat: [29159]: info: standby: master.org can take our foreign resources Feb 19 13:50:43 slave heartbeat: [29194]: info: give up foreign HA resources (standby). Feb 19 13:50:43 slave ResourceManager[29204]: info: Releasing resource group: master.org IPaddr::192.168.3.103 mysqld Feb 19 13:50:43 slave ResourceManager[29204]: info: Running /etc/init.d/mysqld stop Feb 19 13:50:45 slave ResourceManager[29204]: info: Running /etc/ha.d/resource.d/IPaddr 192.168.3.103 stop Feb 19 13:50:45 slave IPaddr[29279]: INFO: Success Feb 19 13:50:45 slave heartbeat: [29194]: info: foreign HA resource release completed (standby). Feb 19 13:50:45 slave heartbeat: [29159]: info: Local standby process completed [foreign]. Feb 19 13:50:46 slave heartbeat: [29159]: WARN: 1 lost packet(s) for [master.org] [162:164] Feb 19 13:50:46 slave heartbeat: [29159]: info: remote resource transition completed. Feb 19 13:50:46 slave heartbeat: [29159]: info: No pkts missing from master.org! Feb 19 13:50:46 slave heartbeat: [29159]: info: Other node completed standby takeover of foreign resources.
现在尝试停止主库的MySQL服务
pkill mysqld
查看日志并无变化,所以得出结论heartbeat只检测心跳也就是只检测设备是否宕机,不会检测MySQL服务,所以我们同样要有一个脚本来检测MySQL服务,如果mysql服务宕掉,则尝试启动服务,若启动服务失败则kill掉heartbeat进程实现故障转移(和上一遍nginx+keepalived原理一致),脚本内容如下:
#!/bin/bash
# filename:mysqlsc.sh
ps aux | grep mysqld | grep -v grep 2> /dev/null 1>&2 # 过滤mysql进程
if [[ $? -eq 0 ]] # 如果过滤有mysql进程会返回0则认为mysql存活
then
sleep 5 # 使脚本进入休眠
else
# 如果nginx没有存活尝试启动mysql,如果失败则杀死heartbeat的进程
/etc/init.d/mysqld start
ps aux | grep mysqld | grep -v grep 2> /dev/null 1>&2
if [[ $? -eq 0 ]]
then
pkill heartbeat
fi
fi
给这个脚本执行权限然后后台运行:
chmod +x mysqlsc.sh nohup sh mysqlsc.sh & # 后台运行
下面来尝试停止主库的heartbeat:
service heartbeat stop
查看从库日志:
heartbeat[29159]: 2012/02/19_14:03:05 info: Received shutdown notice from 'master.org'. heartbeat[29159]: 2012/02/19_14:03:05 info: Resources being acquired from master.org. heartbeat[29308]: 2012/02/19_14:03:05 info: acquire local HA resources (standby). heartbeat[29308]: 2012/02/19_14:03:05 info: local HA resource acquisition completed (standby). heartbeat[29159]: 2012/02/19_14:03:05 info: Standby resource acquisition done [foreign]. heartbeat[29309]: 2012/02/19_14:03:05 info: No local resources [/usr/local/lib/heartbeat/ResourceManager listkeys slave.org] to acquire. harc[29328]: 2012/02/19_14:03:05 info: Running /etc/ha.d/rc.d/status status mach_down[29338]: 2012/02/19_14:03:05 info: Taking over resource group IPaddr::192.168.3.103 ResourceManager[29358]: 2012/02/19_14:03:05 info: Acquiring resource group: master.org IPaddr::192.168.3.103 mysqld IPaddr[29382]: 2012/02/19_14:03:05 INFO: Resource is stopped ResourceManager[29358]: 2012/02/19_14:03:06 info: Running /etc/ha.d/resource.d/IPaddr 192.168.3.103 start IPaddr[29434]: 2012/02/19_14:03:06 INFO: Using calculated nic for 192.168.3.103: eth0 IPaddr[29434]: 2012/02/19_14:03:06 DEBUG: Using calculated netmask for 192.168.3.103: 255.255.255.0 IPaddr[29434]: 2012/02/19_14:03:06 DEBUG: Using calculated broadcast for 192.168.3.103: 192.168.3.255 IPaddr[29434]: 2012/02/19_14:03:06 INFO: eval /sbin/ifconfig eth0:0 192.168.3.103 netmask 255.255.255.0 broadcast 192.168.3.255 IPaddr[29434]: 2012/02/19_14:03:06 DEBUG: Sending Gratuitous Arp for 192.168.3.103 on eth0:0 [eth0] IPaddr[29425]: 2012/02/19_14:03:06 INFO: Success ResourceManager[29358]: 2012/02/19_14:03:06 info: Running /etc/init.d/mysqld start mach_down[29338]: 2012/02/19_14:03:07 info: /usr/local/lib/heartbeat/mach_down: nice_failback: foreign resources acquired mach_down[29338]: 2012/02/19_14:03:07 info: mach_down takeover complete for node master.org. heartbeat[29159]: 2012/02/19_14:03:07 info: mach_down takeover complete. heartbeat[29159]: 2012/02/19_14:03:17 WARN: node master.org: is dead heartbeat[29159]: 2012/02/19_14:03:17 info: Dead node master.org gave up resources. heartbeat[29159]: 2012/02/19_14:03:17 info: Link master.org:eth0 dead.
原文地址：heartbeat实现MySQL双机高可用, 感谢原作者分享。
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1. Use the correct index to speed up data retrieval by reducing the amount of data scanned select*frommployeeswherelast_name='smith'; if you look up a column of a table multiple times, create an index for that column. If you or your app needs data from multiple columns according to the criteria, create a composite index 2. Avoid select * only those required columns, if you select all unwanted columns, this will only consume more server memory and cause the server to slow down at high load or frequency times For example, your table contains columns such as created_at and updated_at and timestamps, and then avoid selecting * because they do not require inefficient query se
The relationship between mysql user and database
Apr 08, 2025 pm 07:15 PM
In MySQL database, the relationship between the user and the database is defined by permissions and tables. The user has a username and password to access the database. Permissions are granted through the GRANT command, while the table is created by the CREATE TABLE command. To establish a relationship between a user and a database, you need to create a database, create a user, and then grant permissions.
Do mysql need to pay
Apr 08, 2025 pm 05:36 PM
MySQL has a free community version and a paid enterprise version. The community version can be used and modified for free, but the support is limited and is suitable for applications with low stability requirements and strong technical capabilities. The Enterprise Edition provides comprehensive commercial support for applications that require a stable, reliable, high-performance database and willing to pay for support. Factors considered when choosing a version include application criticality, budgeting, and technical skills. There is no perfect option, only the most suitable option, and you need to choose carefully according to the specific situation.
Can mysql run on android
Apr 08, 2025 pm 05:03 PM
MySQL cannot run directly on Android, but it can be implemented indirectly by using the following methods: using the lightweight database SQLite, which is built on the Android system, does not require a separate server, and has a small resource usage, which is very suitable for mobile device applications. Remotely connect to the MySQL server and connect to the MySQL database on the remote server through the network for data reading and writing, but there are disadvantages such as strong network dependencies, security issues and server costs.
How to optimize MySQL performance for high-load applications?
Apr 08, 2025 pm 06:03 PM
MySQL database performance optimization guide In resource-intensive applications, MySQL database plays a crucial role and is responsible for managing massive transactions. However, as the scale of application expands, database performance bottlenecks often become a constraint. This article will explore a series of effective MySQL performance optimization strategies to ensure that your application remains efficient and responsive under high loads. We will combine actual cases to explain in-depth key technologies such as indexing, query optimization, database design and caching. 1. Database architecture design and optimized database architecture is the cornerstone of MySQL performance optimization. Here are some core principles: Selecting the right data type and selecting the smallest data type that meets the needs can not only save storage space, but also improve data processing speed.
