作者: 蒋乐兴
微信: jianglegege
官方网站: www.sqlpy.com
自第一个版本的 mysqltools 开源以来,收到了不少用户的反馈;mysqltools8 在此基础上总结了前一个版本的经验与教训,同时也顺应时代的发展增加了许多新的特性,比如支持 docker 这个让 mysqltools8 真正做到了拿来就用,面向 插件实现 一方面让 mysqltools8 的体积从之前的 1.2G 下降到了 30+MB ,另一方面功能上也实现了 热插拔 不管是升级还是扩展新的功能都更加简单。
mysqltools 希望 DBA 能喝着咖啡就把锁事情给做了,并且希望所交付的“输出”健壮到直接不用再管,DBA 节省下来的精力可以去做一些更有价值的事。总的来说我解决好两件事 质量、效率
KFC vs 学校后街的蛋炒饭
KFC 根据既定的流程生产每一个汉堡,假设这个流程下公众对汉堡给出的评分是80分,那么不管哪个 KFC 的店它生产出来的汉堡都稳定在80分;一段时间后 KFC 发现这个流程中可以改进的项,把汉堡的质量提升到81分,那么它就能做到所有的店里的汉堡都能打81分。
学校后街的蛋炒饭,好不好吃这个事难说;因为好多事都影响到它,有可能老板今天心情不好,也有可能是今天客人太多他比较急,这些都会影响到炒饭的质量。有一次我要买两盒,由于去的比较晚,老板只有一个鸡蛋了,你没有猜错! 他就只放了一个。
表面上看 KFC 流程化生产的好处在于它的东西质量有保障,最要命的是 KFC 只做加法,它可以不断提升自己,学校后街的蛋炒饭上周做的好吃,我们没办法确认我下次去吃还是不是那个味。
加法人生
多流水线 vs 手工串行
现在用 MySQL 的很多时候动不动就来个分库分表,先抛开其合理性不谈,就工作量上来说相比单机是要增加了不少。 mysqltools并不希望看到这种工作量线性的增加到 DBA 身上来,为此 mysqltools 一开始就是冲着并行去的。
加量不加工作量
mysqltools 要解决的问题
1、各类 MySQL 环境的建设(单机,主从,MGR,MHA,读写分离)
2、实例生命周期中的备份,监控,事态感知与修复方案下发
3、生命周期结束时的清理与资源回收
mysqltools 提出的方案
1、把多年经验总结的最佳实践编写成 playbook 一来可以减少重复劳动(同时保证质量) 二来可以在此基础上做加法
2、强调监控的重要性,把常规问题的解决方案固化为修复脚本,遇到问题是监控系统自动执行,没出大事不要来烦 DBA
3、最终目标是只要用电环境就是正常的
mysqltools 用到的一些技术
1、ansible 用来做批量管理
2、zabbix 用来做监控和修复方案下发
3、mysql extrabckup meb mysqltools-python 等等 ...
安装
目前mysqltools支持在centos-7.x和以上版本的系统上安装、我们把安装上 mysqltool8 的主机称为管理结点
# 切换到 root 用户
sudo su
# 下载 mysqltools8 安装包并解压
wget https://github.com/Neeky/mysqltools8/archive/master.zip
unzip master.zip
# 进入到 mysqltools8 的目录并执行自动安装脚本
mv mysqltools8-master /usr/local/mysqltools8
cd /usr/local/mysqltools8
bash dependences/install_mysqltools8.sh
source /etc/profile
# 检查是否自动安装上 python-3.7.x
python3 --version
Python 3.7.3
# 检查是否自动安装上 ansible-2.7.10
ansible --version
ansible 2.7.10
配置(ansible 相关)
1、 生成的公钥与私钥
ssh-keygen
# 连续回车
2、 配置到目标主机的互信
ssh-copy-id root@172.16.192.100
3、 增加 ansible 的配置文件
mkdir /etc/ansible
touch /etc/ansible/hosts
echo 'sqlstudio ansible_host=172.16.192.100 ansible_user=root' > /etc/ansible/hosts
完成上面的这些步骤就能在管理机上控制 72.16.192.100 了。
4、 验证一下 ansible 是否配置成功
ansible -m ping sqlstudio
sqlstudio | SUCCESS => {
"changed": false,
"ping": "pong"
}
配置(mysqltools)
新版本的 mysltools 配置非常简单,全局配置就三个
max_memory_size_mb: "{{ 1024 * 512 }}" # 512G内存
mysql_port: 3306
mysql_binary_pkg: "mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz"
#mysql_binary_pkg: "mysql-8.0.16-linux-glibc2.12-x86_64.tar.xz"
1、 mysql_port 指定 MySQL 要监听的地址
2、 mysql_binary_pkg 要使用的 MySQL 二进制包
3、 max_memory_size_mb 这个值的主要目的用来支持单机多实例的,这里是文档的入门阶段不会讲这个值
mysqltools 是插件式的,设计成插件式是为了减小 mysqltools 的体积,mysqltools 中的每一个功能都要有一个“插件”来支持, 拿安装 MySQL 这个事来说支持它的插件就是“MySQL 的二进制安装包” 总的来说所有的插件保存在 sps/插件名/具体的插件版本
事实上现阶段这些配置你可以都不用改,这也是为了 mysqltools 可以拿来就用。你可以进入下一节 安装MySQL单机 体验一下 mysqltools的功能
要安装 MySQL 就要有对应的插件支持,而 MySQL 的支持插件就是 MySQL 的二进制安装包
1、 下载 config.yaml 中指定的 mysql 版本到 mysqltools/sps/mysql/ 目录
mkdir -p /usr/local/mysqltools/sps/mysql
cd /usr/local/mysqltools/sps/mysql
wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz
2、 进入到 mysql 的安装目录
cd /usr/local/mysqltools8/ansible/mysql/
3、 修改 hosts 的值为目标机器(之前配置 ansible 时候设置的 sqlstudio,如果你指定了其它的名字改成对应的就好)
---
- hosts: sqlstudio
remote_user: root
become_user: root
become: yes
vars_files:
4、 自动化单机安装
ansible-playbook install_single.yaml
PLAY [sqlstudio] **********************************************************************************
TASK [Gathering Facts] ****************************************************************************
ok: [sqlstudio]
TASK [create mysql group] *************************************************************************
changed: [sqlstudio]
TASK [create user "mysql3306"] ********************************************************************
changed: [sqlstudio]
TASK [install libaio] *****************************************************************************
changed: [sqlstudio]
TASK [install numactl] ****************************************************************************
changed: [sqlstudio]
TASK [install perl-Data-Dumper] *******************************************************************
changed: [sqlstudio]
TASK [/etc/my-3306.cnf for mysql-8.0.x] ***********************************************************
skipping: [sqlstudio]
TASK [/etc/my-3306.cnf for mysql-5.7.x] ***********************************************************
changed: [sqlstudio]
TASK [transfer mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz to target host(s).] *********************
changed: [sqlstudio]
TASK [generate untar script /tmp/untar_mysql_pkg.sh] **********************************************
changed: [sqlstudio]
TASK [untar mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz] *******************************************
changed: [sqlstudio]
TASK [rm /tmp/untar_mysql_pkg.sh] *****************************************************************
changed: [sqlstudio]
TASK [create libmysqlclient_r.so] *****************************************************************
changed: [sqlstudio]
TASK [update file privileges] *********************************************************************
changed: [sqlstudio]
TASK [config ldconfig] ****************************************************************************
changed: [sqlstudio]
TASK [load so] ************************************************************************************
changed: [sqlstudio]
TASK [conifg header file] *************************************************************************
changed: [sqlstudio]
TASK [rm /tmp/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz] *****************************************
changed: [sqlstudio]
TASK [transfer users.sql to target host(s).] ******************************************************
changed: [sqlstudio]
TASK [transfer init_mysql_data_dir.sh to target host(s).] *****************************************
changed: [sqlstudio]
TASK [init data dir] ******************************************************************************
changed: [sqlstudio]
TASK [/etc/profile] *******************************************************************************
changed: [sqlstudio]
TASK [~/.bash_profile] ****************************************************************************
changed: [sqlstudio]
TASK [~/.bashrc] **********************************************************************************
changed: [sqlstudio]
TASK [config mysqld-3306.service] *****************************************************************
changed: [sqlstudio]
TASK [conifg mysqld-3306 auto start] **************************************************************
changed: [sqlstudio]
TASK [start mysqld-3306] **************************************************************************
changed: [sqlstudio]
TASK [create backup dir] **************************************************************************
changed: [sqlstudio]
TASK [create backup script dir] *******************************************************************
changed: [sqlstudio]
TASK [transfer backup script to target host (mysqldump)] ******************************************
changed: [sqlstudio]
TASK [config backup job (mysqldump)] **************************************************************
changed: [sqlstudio]
PLAY RECAP ****************************************************************************************
sqlstudio : ok=30 changed=29 unreachable=0 failed=0
可以看到就算是一个简单的 MySQL 实例的安装 mysqltools 也执行了大大小小的30个步骤,也许随着之后能力和见识的提升步骤 可能还会更多。
5、 验证一下 MySQL 是否真的安装完成了
# ssh 到被控主机
ssh 172.16.192.100
# 连接一下用于测试 MySQL 服务是否正常
mysql -uroot -pmtls0352 -h127.0.0.1 -P3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.26-log MySQL Community Server (GPL)
Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
1、 为每一个实例都在操作系统层面创建不同的用户
# 如果端口是 3306 那么用户名就是 mysql3306
ps -ef | grep mysql
mysql33+ 24081 1 0 16:24 ? 00:00:01 /usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/bin/mysqld --defaults-file=/etc/my-3306.cnf
root 24402 24381 0 16:50 pts/1 00:00:00 grep --color=auto mysql
cat /etc/passwd | grep mysql33
mysql3306:x:3306:3306::/home/mysql3306:/bin/bash
2、 根据主机的配置(cpu,mem,disk) 自动生成对应的配置文件
[mysql]
auto-rehash
socket =/tmp/mysql-3306.sock # /tmp/mysql.sock
[mysqld]
####: for global
user =mysql3306 # mysql
basedir =/usr/local/mysql-5.7.26-linux-glibc2.12-x86_64 #/usr/local/mysql/
datadir =/database/mysql/data/3306 # /usr/local/mysql/data
server_id =1312 # 0
port =3306 # 3306
character_set_server =utf8 # latin1
log_bin_trust_function_creators =ON # 0
max_prepared_stmt_count =1048576 #
log_timestamps =system # utc
socket =/tmp/mysql-3306.sock # /tmp/mysql.sock
read_only =OFF # off
skip_name_resolve =1 # 0
auto_increment_increment =1 # 1
auto_increment_offset =1 # 1
lower_case_table_names =1 # 0
secure_file_priv = # null
open_files_limit =102000 # 1024
thread_cache_size =16 # 9
max_connections =151 # 151
####: for table cache
table_open_cache =4000 # 2000
table_definition_cache =2000 # 1400
table_open_cache_instances =16 # 16
####: for binlog
binlog_format =ROW # row
log_bin =mysql-bin # off
binlog_rows_query_log_events =ON # off
log_slave_updates =ON # off
expire_logs_days =7 # 0
binlog_cache_size =64k # 65536(64k)
binlog_checksum =none # CRC32
sync_binlog =1 # 1
slave-preserve-commit-order =ON #
####: for error-log
log_error =err.log # /usr/local/mysql/data/localhost.localdomain.err
####: for general-log
general_log =OFF # off
general_log_file =general.log # hostname.log
####: for slow query log
slow_query_log =ON # off
slow_query_log_file =slow.log # hostname.log
log_queries_not_using_indexes =OFF # off
long_query_time =2.0 # 10.000000
####: for gtid
gtid_executed_compression_period =1000 # 1000
gtid_mode =ON # off
enforce_gtid_consistency =ON # off
####: for replication
skip_slave_start =0 #
master_info_repository =table # file
relay_log_info_repository =table # file
slave_parallel_type =logical_clock # database | LOGICAL_CLOCK
slave_parallel_workers =4 # 0
rpl_semi_sync_master_enabled =1 # 0
rpl_semi_sync_slave_enabled =1 # 0
rpl_semi_sync_master_timeout =1000 # 1000(1 second)
plugin_load_add =semisync_master.so #
plugin_load_add =semisync_slave.so #
binlog_group_commit_sync_delay =200 # 0 200(0.02% seconde)
binlog_group_commit_sync_no_delay_count = 10 # 0
binlog_transaction_dependency_tracking = WRITESET # COMMIT_ORDER | WRITESET
transaction_write_set_extraction = XXHASH64
####: for innodb
default_storage_engine =innodb # innodb
default_tmp_storage_engine =innodb # innodb
innodb_data_file_path =ibdata1:256M:autoextend # ibdata1:12M:autoextend
innodb_temp_data_file_path =ibtmp1:64M:autoextend # ibtmp1:12M:autoextend
innodb_buffer_pool_filename =ib_buffer_pool # ib_buffer_pool
innodb_log_group_home_dir =./ # ./
innodb_log_files_in_group =8 # 2
innodb_log_file_size =128M # 50331648(48M)
innodb_file_per_table =ON # on
innodb_online_alter_log_max_size =128M # 134217728(128M)
innodb_open_files =64000 # 2000
innodb_page_size =16k # 16384(16k)
innodb_thread_concurrency =0 # 0
innodb_read_io_threads =4 # 4
innodb_write_io_threads =4 # 4
innodb_purge_threads =4 # 4(garbage collection)
innodb_page_cleaners =4 # 4(flush lru list)
innodb_print_all_deadlocks =ON # off
innodb_deadlock_detect =ON # on
innodb_lock_wait_timeout =50 # 50
innodb_spin_wait_delay =6 # 6
innodb_autoinc_lock_mode =2 # 1
innodb_flush_sync =OFF # on
innodb_io_capacity =4000 # 200
innodb_io_capacity_max =20000 # 2000
#--------Persistent Optimizer Statistics
innodb_stats_auto_recalc =ON # on
innodb_stats_persistent =ON # on
innodb_stats_persistent_sample_pages =20 # 20
innodb_adaptive_hash_index =ON # on
innodb_change_buffering =all # all
innodb_change_buffer_max_size =25 # 25
innodb_flush_neighbors =0 # 1
innodb_flush_method =O_DIRECT #
innodb_doublewrite =ON # on
innodb_log_buffer_size =64M # 16777216(16M)
innodb_flush_log_at_timeout =1 # 1
innodb_flush_log_at_trx_commit =1 # 1
innodb_buffer_pool_size =896M # 134217728(128M)
innodb_buffer_pool_instances =1 # 1
autocommit =ON # 1
#--------innodb scan resistant
innodb_old_blocks_pct =37 # 37
innodb_old_blocks_time =1000 # 1000
#--------innodb read ahead
innodb_read_ahead_threshold =56 # 56 (0..64)
innodb_random_read_ahead =off # OFF
#--------innodb buffer pool state
innodb_buffer_pool_dump_pct =50 # 25
innodb_buffer_pool_dump_at_shutdown =ON # ON
innodb_buffer_pool_load_at_startup =ON # ON
#### for performance_schema
performance_schema =on # on
performance_schema_consumer_global_instrumentation =on # on
performance_schema_consumer_thread_instrumentation =on # on
performance_schema_consumer_events_stages_current =on # off
performance_schema_consumer_events_stages_history =on # off
performance_schema_consumer_events_stages_history_long =off # off
performance_schema_consumer_statements_digest =on # on
performance_schema_consumer_events_statements_current =on # on
performance_schema_consumer_events_statements_history =on # on
performance_schema_consumer_events_statements_history_long =off # off
performance_schema_consumer_events_waits_current =on # off
performance_schema_consumer_events_waits_history =on # off
performance_schema_consumer_events_waits_history_long =off # off
performance-schema-instrument ='memory/%=COUNTED'
# -- ~ _ ~ ~ _ ~ ~ _ ~ --
# base on mysql-5.7.24
# generated by https://www.sqlpy.com 2019年5月22日 15:39
# wechat: jianglegege
# email: 1721900707@qq.com
# -- ~ _ ~ --
3、 自动导出相应的动态库和PATH环境变量头文件
cat /etc/ld.so.conf.d/mysql-5.7.26-linux-glibc2.12-x86_64.conf
/usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/lib/
cat /etc/profile | grep mysql
export PATH=/usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/bin/:$PATH
4、 systemd 服务管理
cat /usr/lib/systemd/system/mysqld-3306.service
[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
User=mysql3306
Group=mysql
ExecStart=/usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/bin/mysqld --defaults-file=/etc/my-3306.cnf
LimitNOFILE = 102400
Environment=MYSQLD_PARENT_PID=1
#Restart=on-failure
#RestartPreventExitStatus=1
5、 创建自动备份任务
su mysql3306
[mysql3306@sqlstudio tmp]$ crontab -l
#Ansible: mysql-3306-auto-backup
0 2 * * * /usr/local/.mtlsscripts/3306-mysqldump-backup.sh
其它更加精细的行为是由 mysqltools8/ansible/mysql/vars/mysql.yaml 这个配置文件来控制的
#mysql configure
mysql_user: "mysql{{mysql_port}}"
mysql_group: mysql
mysql_uid: "{{mysql_port}}"
mysql_gid: 3306
mysql_backup_tool: "mysqldump"
mysql_backup_crontab_day: "*"
mysql_backup_crontab_hour: "2"
mysql_backup_crontab_minute: "0"
mysql_base_dir: "/usr/local/{{ mysql_binary_pkg | replace('.tar.gz','') | replace('.tar.xz','') }}"
mysql_data_dir: "/database/mysql/data/{{mysql_port}}"
mysql_version: "{{ mysql_binary_pkg | replace('.tar.gz','') | replace('.tar.xz','') }}"
mysql_backup_dir: "/backup/mysql/{{mysql_port}}"
mysql_backup_script_dir: "/usr/local/.mtlsscripts"
mysql_root_pwd: 'mtls0352'
mysql_monitor_user: 'monitor'
mysql_monitor_pwd: 'monitor0352'
mysql_dumper_user: 'dumper'
mysql_dumper_pwd: 'dumper0352'
mysql_extra_user: 'extrabackuper'
mysql_extra_pwd: 'extra0352'
mysql_binlog_format: "row"
mysql_xport: "{{ mysql_port * 10 }}"
mysql_mgrport: "{{ mysql_port * 10 + 1 }}"
mysql_admin_port: "{{ mysql_port * 10 + 2 }}"
可以看到其它的参数基本上是由全局的 mysql_port mysql_binary_pkg 这两个参数来决定的,通常来说你可以自定义一下用户的密码和备份时间(其实也没有必要改)
通过前面 安装MySQL单机 下面看一下单机多实例在 mysqltools 做起来有多简单,实事上只要改一下全局配置中的 port 就行了
1、 改全局配置文件 mysqltools8/config.yaml 中 mysql_port 的值(在这里我改成了 3308)
max_memory_size_mb: "{{ 1024 * 512 }}" # 512G内存
mysql_port: 3308
mysql_binary_pkg: "mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz"
#mysql_binary_pkg: "mysql-8.0.16-linux-glibc2.12-x86_64.tar.xz"
2、 指定实例的最大可分配内存 max_memory_size_mb 这个参数如果比主机的内存要大,那么最终以主机的内存为准;如果比主机内存要小那么以 max_memory_size_mb 为准。我在这里把新实例的内存设置为 1G 也就是改成 1024 * 1
max_memory_size_mb: "{{ 1024 * 1 }}" # 1G内存
mysql_port: 3308
mysql_binary_pkg: "mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz"
#mysql_binary_pkg: "mysql-8.0.16-linux-glibc2.12-x86_64.tar.xz"
3、 执行安装
ansible-playbook install_single.yaml
PLAY [sqlstudio] **********************************************************************************
TASK [Gathering Facts] ****************************************************************************
ok: [sqlstudio]
TASK [create mysql group] *************************************************************************
ok: [sqlstudio]
TASK [create user "mysql3308"] ********************************************************************
changed: [sqlstudio]
TASK [install libaio] *****************************************************************************
ok: [sqlstudio]
TASK [install numactl] ****************************************************************************
ok: [sqlstudio]
TASK [install perl-Data-Dumper] *******************************************************************
ok: [sqlstudio]
TASK [/etc/my-3308.cnf for mysql-8.0.x] ***********************************************************
skipping: [sqlstudio]
TASK [/etc/my-3308.cnf for mysql-5.7.x] ***********************************************************
changed: [sqlstudio]
TASK [transfer mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz to target host(s).] *********************
changed: [sqlstudio]
TASK [generate untar script /tmp/untar_mysql_pkg.sh] **********************************************
changed: [sqlstudio]
TASK [untar mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz] *******************************************
changed: [sqlstudio]
TASK [rm /tmp/untar_mysql_pkg.sh] *****************************************************************
changed: [sqlstudio]
TASK [create libmysqlclient_r.so] *****************************************************************
ok: [sqlstudio]
TASK [update file privileges] *********************************************************************
changed: [sqlstudio]
TASK [config ldconfig] ****************************************************************************
ok: [sqlstudio]
TASK [load so] ************************************************************************************
changed: [sqlstudio]
TASK [conifg header file] *************************************************************************
ok: [sqlstudio]
TASK [rm /tmp/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz] *****************************************
changed: [sqlstudio]
TASK [transfer users.sql to target host(s).] ******************************************************
ok: [sqlstudio]
TASK [transfer init_mysql_data_dir.sh to target host(s).] *****************************************
changed: [sqlstudio]
TASK [init data dir] ******************************************************************************
changed: [sqlstudio]
TASK [/etc/profile] *******************************************************************************
ok: [sqlstudio]
TASK [~/.bash_profile] ****************************************************************************
changed: [sqlstudio]
TASK [~/.bashrc] **********************************************************************************
changed: [sqlstudio]
TASK [config mysqld-3308.service] *****************************************************************
changed: [sqlstudio]
TASK [conifg mysqld-3308 auto start] **************************************************************
changed: [sqlstudio]
TASK [start mysqld-3308] **************************************************************************
changed: [sqlstudio]
TASK [create backup dir] **************************************************************************
changed: [sqlstudio]
TASK [create backup script dir] *******************************************************************
changed: [sqlstudio]
TASK [transfer backup script to target host (mysqldump)] ******************************************
changed: [sqlstudio]
TASK [config backup job (mysqldump)] **************************************************************
changed: [sqlstudio]
PLAY RECAP ****************************************************************************************
sqlstudio : ok=30 changed=20 unreachable=0 failed=0
4、 实例是否启动
ps -ef | grep mysql
mysql33+ 24081 1 0 16:24 ? 00:00:01 /usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/bin/mysqld --defaults-file=/etc/my-3306.cnf
mysql33+ 32415 1 0 16:25 ? 00:00:00 /usr/local/mysql-5.7.26-linux-glibc2.12-x86_64/bin/mysqld --defaults-file=/etc/my-3308.cnf
mysql -uroot -pmtls0352 -h127.0.0.1 -P3308
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.26-log MySQL Community Server (GPL)
Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> select @@innodb_buffer_pool_size /1024/1024;
+--------------------------------------+
| @@innodb_buffer_pool_size /1024/1024 |
+--------------------------------------+
| 256.00000000 |
+--------------------------------------+
1 row in set (0.00 sec)
可以看到当你指定主机的最大可分配内存为 1G 时 mysqltools 给 innodb_buffer_pool_size 分配了 256M。