macos的mysql没有my.cnf文件，特补充在此

官网说&＃xff1a;从5.7.18开始不在二进制包中提供my-default.cnf文件。参考&＃xff1a;https://dev.mysql.com/doc/refman/5.7/en/binary-installation.html

经过测试&＃xff0c;在5.7.18版本中&＃xff0c;使用tar.gz安装时&＃xff0c;也就是压缩包解压出来安装这种&＃xff0c;已经不再需要my.cnf文件也能正常运行。

my.cnf文件就是把在命令行上启动MySQL时后面的参数用cnf文件配置好&＃xff0c;那么下载启动时就不再需要在命令上加如参数。

这个my.cnf文件可以是自定义位置&＃xff0c;也可以使用如下默认的位置&＃xff0c;只要放在默认位置&＃xff0c;MySQL自动识别&＃xff08;通过deb或者APT源安装的&＃xff0c;初始位置在下方列表&＃xff09;&＃xff1a;

本次使用安装包安装的版本为8.0.19 系统为MACOS  10.15.3

以上的详细说明可以参考官方解释&＃xff1a;https://dev.mysql.com/doc/refman/5.7/en/option-files.html

总之&＃xff0c;无论是使用APT源安装还是deb包安装&＃xff0c;或者二进制&＃xff08;压缩包tar.gz&＃xff09;包安装的&＃xff0c;都可以通过my.cnf文件进行配置来达到MySQL的启动配置及调优。

由于在5.7.18开始&＃xff0c;二进制包不再包含示例文件my-default.cnf&＃xff0c;所以我从5.7.17版本中提取了样例&＃xff0c;但是发现里面也没有太多项配置&＃xff0c;my-default.cnf内容如下&＃xff1a;

# Example MySQL config file for medium systems. # # This is for a system with little memory (32M - 64M) where MySQL plays # an important part, or systems up to 128M where MySQL is used together with # other programs (such as a web server) # # MySQL programs look for option files in a set of # locations which depend on the deployment platform. # You can copy this option file to one of those # locations. For information about these locations, see: # http://dev.mysql.com/doc/mysql/en/option-files.html # # In this file, you can use all long options that a program supports. # If you want to know which options a program supports, run the program # with the "--help" option. # The following options will be passed to all MySQL clients [client]default-character-set&＃61;utf8#password &＃61; your_password port &＃61; 3306 socket &＃61; /tmp/mysql.sock # Here follows entries for some specific programs # The MySQL server [mysqld]character-set-server&＃61;utf8init_connect&＃61;&＃39;SET NAMES utf8port &＃61; 3306 socket &＃61; /tmp/mysql.sock skip-external-locking key_buffer_size &＃61; 16M max_allowed_packet &＃61; 1M table_open_cache &＃61; 64 sort_buffer_size &＃61; 512K net_buffer_length &＃61; 8K read_buffer_size &＃61; 256K read_rnd_buffer_size &＃61; 512K myisam_sort_buffer_size &＃61; 8M character-set-server&＃61;utf8 init_connect&＃61;&＃39;SET NAMES utf8&＃39;
# Don&＃39;t listen on a TCP/IP port at all. This can be a security enhancement,
# if all processes that need to connect to mysqld run on the same host.
# All interaction with mysqld must be made via Unix sockets or named pipes.
# Note that using this option without enabling named pipes on Windows
# (via the "enable-named-pipe" option) will render mysqld useless!
#
#skip-networking # Replication Master Server (default) # binary logging is required for replication log-bin&＃61;mysql-bin # binary logging format - mixed recommended binlog_format&＃61;mixed # required unique id between 1 and 2^32 - 1 # defaults to 1 if master-host is not set # but will not function as a master if omitted server-id &＃61; 1 # Replication Slave (comment out master section to use this) # # To configure this host as a replication slave, you can choose between # two methods : # # 1) Use the CHANGE MASTER TO command (fully described in our manual) - # the syntax is: # # CHANGE MASTER TO MASTER_HOST&＃61;, MASTER_PORT&＃61;, # MASTER_USER&＃61;, MASTER_PASSWORD&＃61; ; # # where you replace , , by quoted strings and # by the master&＃39;s port number (3306 by default). # # Example: # # CHANGE MASTER TO MASTER_HOST&＃61;&＃39;125.564.12.1&＃39;, MASTER_PORT&＃61;3306, # MASTER_USER&＃61;&＃39;joe&＃39;, MASTER_PASSWORD&＃61;&＃39;secret&＃39;; # # OR # # 2) Set the variables below. However, in case you choose this method, then # start replication for the first time (even unsuccessfully, for example # if you mistyped the password in master-password and the slave fails to # connect), the slave will create a master.info file, and any later # change in this file to the variables&＃39; values below will be ignored and # overridden by the content of the master.info file, unless you shutdown # the slave server, delete master.info and restart the slaver server. # For that reason, you may want to leave the lines below untouched # (commented) and instead use CHANGE MASTER TO (see above) # # required unique id between 2 and 2^32 - 1 # (and different from the master) # defaults to 2 if master-host is set # but will not function as a slave if omitted #server-id &＃61; 2 # # The replication master for this slave - required #master-host &＃61; # # The username the slave will use for authentication when connecting # to the master - required #master-user &＃61; # # The password the slave will authenticate with when connecting to # the master - required #master-password &＃61; # # The port the master is listening on. # optional - defaults to 3306 #master-port &＃61; # # binary logging - not required for slaves, but recommended #log-bin&＃61;mysql-bin # Uncomment the following if you are using InnoDB tables #innodb_data_home_dir &＃61; /usr/local/mysql/data #innodb_data_file_path &＃61; ibdata1:10M:autoextend #innodb_log_group_home_dir &＃61; /usr/local/mysql/data # You can set .._buffer_pool_size up to 50 - 80 % # of RAM but beware of setting memory usage too high #innodb_buffer_pool_size &＃61; 16M #innodb_additional_mem_pool_size &＃61; 2M # Set .._log_file_size to 25 % of buffer pool size #innodb_log_file_size &＃61; 5M #innodb_log_buffer_size &＃61; 8M #innodb_flush_log_at_trx_commit &＃61; 1 #innodb_lock_wait_timeout &＃61; 50 [mysqldump] quick max_allowed_packet &＃61; 16M [mysql] no-auto-rehash # Remove the next comment character if you are not familiar with SQL #safe-updates default-character-set&＃61;utf8 [myisamchk] key_buffer_size &＃61; 20M sort_buffer_size &＃61; 20M read_buffer &＃61; 2M write_buffer &＃61; 2M [mysqlhotcopy] interactive-timeout

可以自行建立这个文档&＃xff0c;复制到 /usr/local/mysql/support_files目录下

其实&＃xff0c;这些项都是命令行的参数&＃xff0c;在官网上可以从这个页面https://dev.mysql.com/doc/refman/5.7/en/option-files.html为入口&＃xff0c;找到需要配置的项按需要进行配置。

下面这个是来自http://www.fx114.net/qa-220-164752.aspx提供的my.cnf示例&＃xff1a;

[client]
port &＃61; 3306
socket &＃61; /tmp/mysql.sock[mysqld]###############################基础设置######################################Mysql服务的唯一编号 每个mysql服务Id需唯一
server-id &＃61; 1#服务端口号 默认3306
port &＃61; 3306#mysql安装根目录
basedir &＃61; /opt/mysql#mysql数据文件所在位置
datadir &＃61; /opt/mysql/data#临时目录 比如load data infile会用到
tmpdir &＃61; /tmp#设置socke文件所在目录
socket &＃61; /tmp/mysql.sock#主要用于MyISAM存储引擎,如果多台服务器连接一个数据库则建议注释下面内容
skip-external-locking#只能用IP地址检查客户端的登录&＃xff0c;不用主机名
skip_name_resolve &＃61; 1#事务隔离级别&＃xff0c;默认为可重复读&＃xff0c;mysql默认可重复读级别&＃xff08;此级别下可能参数很多间隙锁&＃xff0c;影响性能&＃xff09;
transaction_isolation &＃61; READ-COMMITTED#数据库默认字符集,主流字符集支持一些特殊表情符号&＃xff08;特殊表情符占用4个字节&＃xff09;
character-set-server &＃61; utf8mb4#数据库字符集对应一些排序等规则&＃xff0c;注意要和character-set-server对应
collation-server &＃61; utf8mb4_general_ci#设置client连接mysql时的字符集,防止乱码
init_connect&＃61;&＃39;SET NAMES utf8mb4&＃39;#是否对sql语句大小写敏感&＃xff0c;1表示不敏感
lower_case_table_names &＃61; 1#最大连接数
max_connections &＃61; 400#最大错误连接数
max_connect_errors &＃61; 1000#TIMESTAMP如果没有显示声明NOT NULL&＃xff0c;允许NULL值
explicit_defaults_for_timestamp &＃61; true#SQL数据包发送的大小&＃xff0c;如果有BLOB对象建议修改成1G
max_allowed_packet &＃61; 128M#MySQL连接闲置超过一定时间后(单位&＃xff1a;秒)将会被强行关闭
#MySQL默认的wait_timeout 值为8个小时, interactive_timeout参数需要同时配置才能生效
interactive_timeout &＃61; 1800
wait_timeout &＃61; 1800#内部内存临时表的最大值 &＃xff0c;设置成128M。
#比如大数据量的group by ,order by时可能用到临时表&＃xff0c;
#超过了这个值将写入磁盘&＃xff0c;系统IO压力增大
tmp_table_size &＃61; 134217728
max_heap_table_size &＃61; 134217728#禁用mysql的缓存查询结果集功能
#后期根据业务情况测试决定是否开启
#大部分情况下关闭下面两项
query_cache_size &＃61; 0
query_cache_type &＃61; 0#####################用户进程分配到的内存设置BEGIN###############################每个session将会分配参数设置的内存大小
#用于表的顺序扫描&＃xff0c;读出的数据暂存于read_buffer_size中&＃xff0c;当buff满时或读完&＃xff0c;将数据返回上层调用者
#一般在128kb ~ 256kb,用于MyISAM
#read_buffer_size &＃61; 131072
#用于表的随机读取&＃xff0c;当按照一个非索引字段排序读取时会用到&＃xff0c;
#一般在128kb ~ 256kb,用于MyISAM
#read_rnd_buffer_size &＃61; 262144
#order by或group by时用到#建议先调整为2M&＃xff0c;后期观察调整
sort_buffer_size &＃61; 2097152#一般数据库中没什么大的事务&＃xff0c;设成1~2M&＃xff0c;默认32kb
binlog_cache_size &＃61; 524288########################用户进程分配到的内存设置END#############################在MySQL暂时停止响应新请求之前的短时间内多少个请求可以被存在堆栈中
#官方建议back_log &＃61; 50 &＃43; (max_connections / 5),封顶数为900
back_log &＃61; 130############################日志设置###########################################数据库错误日志文件
log_error &＃61; error.log#慢查询sql日志设置
slow_query_log &＃61; 1
slow_query_log_file &＃61; slow.log#检查未使用到索引的sql
log_queries_not_using_indexes &＃61; 1#针对log_queries_not_using_indexes开启后&＃xff0c;记录慢sql的频次、每分钟记录的条数
log_throttle_queries_not_using_indexes &＃61; 5#作为从库时生效,从库复制中如何有慢sql也将被记录
log_slow_slave_statements &＃61; 1#慢查询执行的秒数&＃xff0c;必须达到此值可被记录
long_query_time &＃61; 8#检索的行数必须达到此值才可被记为慢查询
min_examined_row_limit &＃61; 100#mysql binlog日志文件保存的过期时间&＃xff0c;过期后自动删除
expire_logs_days &＃61; 5############################主从复制设置######################################开启mysql binlog功能
log-bin&＃61;mysql-bin#binlog记录内容的方式&＃xff0c;记录被操作的每一行
binlog_format &＃61; ROW#对于binlog_format &＃61; ROW模式时&＃xff0c;减少记录日志的内容&＃xff0c;只记录受影响的列
binlog_row_image &＃61; minimal#master status and connection information输出到表mysql.slave_master_info中
master_info_repository &＃61; TABLE#the slave&＃39;s position in the relay logs输出到表mysql.slave_relay_log_info中
relay_log_info_repository &＃61; TABLE#作为从库时生效,想进行级联复制&＃xff0c;则需要此参数
log_slave_updates#作为从库时生效,中继日志relay-log可以自我修复
relay_log_recovery &＃61; 1#作为从库时生效,主从复制时忽略的错误
slave_skip_errors &＃61; ddl_exist_errors#####################redo log和binlog的关系设置BEGIN##########################(步骤1) prepare dml相关的SQL操作&＃xff0c;然后将redo log buff中的缓存持久化到磁盘
#(步骤2)如果前面prepare成功&＃xff0c;那么再继续将事务日志持久化到binlog
#(步骤3)如果前面成功&＃xff0c;那么在redo log里面写上一个commit记录
#当innodb_flush_log_at_trx_commit和sync_binlog都为1时是最安全的&＃xff0c;
#在mysqld服务崩溃或者服务器主机crash的情况下&＃xff0c;binary log只有可能丢失最多一个语句或者一个事务。
#但是都设置为1时会导致频繁的io操作&＃xff0c;因此该模式也是最慢的一种方式。
#当innodb_flush_log_at_trx_commit设置为0&＃xff0c;mysqld进程的崩溃会导致上一秒钟所有事务数据的丢失。
#当innodb_flush_log_at_trx_commit设置为2&＃xff0c;只有在操作系统崩溃或者系统掉电的情况下&＃xff0c;上一秒钟所有事务数据才可能丢失。#commit事务时,控制redo log buff持久化磁盘的模式 默认为1
innodb_flush_log_at_trx_commit &＃61; 2#commit事务时,控制写入mysql binlog日志的模式 默认为0
#innodb_flush_log_at_trx_commit和sync_binlog都为1时&＃xff0c;mysql最为安全但性能上压力也是最大
sync_binlog &＃61; 1####################redo log和binlog的关系设置END########################################################Innodb设置######################################数据块的单位8k&＃xff0c;默认是16k&＃xff0c;16kCPU压力稍小&＃xff0c;8k对select的吞吐量大
#innodb_page_size的参数值也影响最大索引长度&＃xff0c;8k比16k的最大索引长度小
#innodb_page_size &＃61; 8192#一般设置物理存储的60% ~ 70%
innodb_buffer_pool_size &＃61; 1G#5.7.6之后默认16M
#innodb_log_buffer_size &＃61; 16777216#该参数针对unix、linux&＃xff0c;window上直接注释该参数.默认值为NULL
#O_DIRECT减少操作系统级别VFS的缓存和Innodb本身的buffer缓存之间的冲突
innodb_flush_method &＃61; O_DIRECT#此格式支持压缩, 5.7.7之后为默认值
innodb_file_format &＃61; Barracuda#CPU多核处理能力设置&＃xff0c;假设CPU是2颗4核的&＃xff0c;设置如下
#读多&＃xff0c;写少可以设成2:6的比例
innodb_write_io_threads &＃61; 4
innodb_read_io_threads &＃61; 4#提高刷新脏页数量和合并插入数量&＃xff0c;改善磁盘I/O处理能力
#默认值200&＃xff08;单位&＃xff1a;页&＃xff09;
#可根据磁盘近期的IOPS确定该值
innodb_io_capacity &＃61; 500#为了获取被锁定的资源最大等待时间&＃xff0c;默认50秒&＃xff0c;超过该时间会报如下错误:
# ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
innodb_lock_wait_timeout &＃61; 30#调整buffer pool中最近使用的页读取并dump的百分比,通过设置该参数可以减少转储的page数
innodb_buffer_pool_dump_pct &＃61; 40#设置redoLog文件所在目录, redoLog记录事务具体操作内容
innodb_log_group_home_dir &＃61; /opt/mysql/redolog/#设置undoLog文件所在目录, undoLog用于事务回滚操作
innodb_undo_directory &＃61; /opt/mysql/undolog/#在innodb_log_group_home_dir中的redoLog文件数, redoLog文件内容是循环覆盖写入。
innodb_log_files_in_group &＃61; 3#MySql5.7官方建议尽量设置的大些&＃xff0c;可以接近innodb_buffer_pool_size的大小
#之前设置该值较大时可能导致mysql宕机恢复时间过长&＃xff0c;现在恢复已经加快很多了
#该值减少脏数据刷新到磁盘的频次
#最大值innodb_log_file_size * innodb_log_files_in_group <&＃61; 512GB,单文件<&＃61;256GB
innodb_log_file_size &＃61; 1024M#设置undoLog文件所占空间可以回收
#5.7之前的MySql的undoLog文件一直增大无法回收
innodb_undo_log_truncate &＃61; 1
innodb_undo_tablespaces &＃61; 3
innodb_undo_logs &＃61; 128#5.7.7默认开启该参数 控制单列索引长度最大达到3072
#innodb_large_prefix &＃61; 1#5.7.8默认为4个, Inodb后台清理工作的线程数
#innodb_purge_threads &＃61; 4#通过设置配置参数innodb_thread_concurrency来限制并发线程的数量&＃xff0c;
#一旦执行线程的数量达到这个限制&＃xff0c;额外的线程在被放置到对队列中之前&＃xff0c;会睡眠数微秒&＃xff0c;
#可以通过设定参数innodb_thread_sleep_delay来配置睡眠时间
#该值默认为0,在官方doc上&＃xff0c;对于innodb_thread_concurrency的使用&＃xff0c;也给出了一些建议:
#(1)如果一个工作负载中&＃xff0c;并发用户线程的数量小于64&＃xff0c;建议设置innodb_thread_concurrency&＃61;0&＃xff1b;
#(2)如果工作负载一直较为严重甚至偶尔达到顶峰&＃xff0c;建议先设置innodb_thread_concurrency&＃61;128,
###并通过不断的降低这个参数&＃xff0c;96, 80, 64等等&＃xff0c;直到发现能够提供最佳性能的线程数
#innodb_thread_concurrency &＃61; 0#强所有发生的死锁错误信息记录到error.log中&＃xff0c;之前通过命令行只能查看最近一次死锁信息
innodb_print_all_deadlocks &＃61; 1############################其他设置########################################[mysqldump]
quick
max_allowed_packet &＃61; 128M[mysql]
no-auto-rehash[myisamchk]
key_buffer_size &＃61; 20M
sort_buffer_size &＃61; 256k
read_buffer &＃61; 2M
write_buffer &＃61; 2M[mysqlhotcopy]
interactive-timeout[mysqld_safe]
#增加每个进程的可打开文件数量
open-files-limit &＃61; 28192

提示&＃xff1a;上述的文件不建议全部拷贝使用&＃xff0c;当需要哪块时单独复制是最好的&＃xff0c;因为每台服务器的需求都不一样。

注意&＃xff1a;官方建议二进制文件是放置在/usr/local下&＃xff0c;my.cnf当然可以放在默认位置之后&＃xff0c;还可以直接指定在二进制文件夹中等。然后现在新版的Linux是建议第三方软件放在/opt下&＃xff0c;我觉都可以&＃xff0c;建议按照官网的来配置最好&＃xff0c;方便排查问题。