第七节：MySQL 的配置文件

一、MySQL的配置文件

　　1、my.ini 是什么

　　　　my.ini是MySQL数据库中使用的配置文件，修改这个文件可以达到更新配置的目的。

　　2、my.ini 存放在哪里

　　　　（1）以MySQL5.5为例，my.ini 存放在MySQL的安装的根目录

　　　　　　

 

 

 　　　　（2）以 MySQL5.6 | MySQL5.7 | MySQL 8.0 的配置文件存放在 C:\ProgramData\下面：

　　　　　　

 

 

 　　　　　　　　

 

 　　　　　　　　

 

 　　　　　　　　

 

　　　　　　注意：修改完配置文件，一定需要重复 MySQL 服务。

二、my.ini 的配置文件内容

# MySQL Server Instance Configuration File  2 # ----------------------------------------------------------------------
# Generated by the MySQL Server Instance Configuration Wizard  4 #  5 #  6 # Installation Instructions  7 # ----------------------------------------------------------------------
#  9 # On Linux you can copy this file to /etc/my.cnf to set global options,  10 # mysql-data-dir/my.cnf to set server-specific options  11 # (@localstatedir@ for this installation) or to  12 # ~/.my.cnf to set user-specific options.  13 #  14 # On Windows you should keep this file in the installation directory  15 # of your server (e.g. C:\Program Files\MySQL\MySQL Server X.Y). To  16 # make sure the server reads the config file use the startup option  17 # "--defaults-file".  18 #  19 # To run run the server from the command line, execute this in a  20 # command line shell, e.g.  21 # mysqld --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#  23 # To install the server as a Windows service manually, execute this in a  24 # command line shell, e.g.  25 # mysqld --install MySQLXY --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#  27 # And then execute this in a command line shell to start the server, e.g.  28 # net start MySQLXY  29 #  30 #  31 # Guildlines for editing this file  32 # ----------------------------------------------------------------------
#  34 # In this file, you can use all long options that the program supports.  35 # If you want to know the options a program supports, start the program  36 # with the "--help" option.  37 #  38 # More detailed information about the individual options can also be  39 # found in the manual.  40 #  41 #  42 # CLIENT SECTION  43 # ----------------------------------------------------------------------
#  45 # The following options will be read by MySQL client applications.  46 # Note that only client applications shipped by MySQL are guaranteed  47 # to read this section. If you want your own MySQL client program to  48 # honor these values, you need to specify it as an option during the  49 # MySQL client library initialization.  50 #  51 [client]  52 
port=3306

[mysql]  56 
default-character-set=utf8  58 

# SERVER SECTION  61 # ----------------------------------------------------------------------
#  63 # The following options will be read by the MySQL Server. Make sure that  64 # you have installed the server correctly (see above) so it reads this 
# file.  66 #  67 [mysqld]  68 
# The TCP/IP Port the MySQL Server will listen on  70 port=3306


#Path to installation directory. All paths are usually resolved relative to this.  74 basedir="D:/MySQL/MySQL Server 5.5/"

#Path to the database root  77 datadir="D:/MySQL_Data/MySQL Server 5.5/Data/"

# The default character set that will be used when a new schema or table is
# created and no character set is defined  81 character-set-server=utf8  82 
# The default storage engine that will be used when create new tables when  84 default-storage-engine=INNODB  85 
# Set the SQL mode to strict  87 sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

# The maximum amount of concurrent sessions the MySQL server will  90 # allow. One of these connections will be reserved for a user with  91 # SUPER privileges to allow the administrator to login even if the  92 # connection limit has been reached.  93 max_connections=100

# Query cache is used to cache SELECT results and later return them  96 # without actual executing the same query once again. Having the query  97 # cache enabled may result in significant speed improvements, if your  98 # have a lot of identical queries and rarely changing tables. See the  99 # "Qcache_lowmem_prunes" status variable to check if the current value 100 # is high enough for your load. 101 # Note: In case your tables change very often or if your queries are 102 # textually different every time, the query cache may result in a 103 # slowdown instead of a performance improvement. 104 query_cache_size=15M 105 
# The number of open tables for all threads. Increasing this value 107 # increases the number of file descriptors that mysqld requires. 108 # Therefore you have to make sure to set the amount of open files 109 # allowed to at least 4096 in the variable "open-files-limit" in
# section [mysqld_safe] 111 table_cache=256

# Maximum size for internal (in-memory) temporary tables. If a table 114 # grows larger than this value, it is automatically converted to disk 115 # based table This limitation is for a single table. There can be many 116 # of them. 117 tmp_table_size=18M 118 

# How many threads we should keep in a cache for reuse. When a client 121 # disconnects, the client's threads are put in the cache if there aren't 122 # more than thread_cache_size threads from before. This greatly reduces 123 # the amount of thread creations needed if you have a lot of new
# connections. (Normally this doesn't give a notable performance
# improvement if you have a good thread implementation.) 126 thread_cache_size=8

#*** MyISAM Specific options 129 
# The maximum size of the temporary file MySQL is allowed to use while
# recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE. 132 # If the file-size would be bigger than this, the index will be created 133 # through the key cache (which is slower). 134 myisam_max_sort_file_size=100G 135 
# If the temporary file used for fast index creation would be bigger 137 # than using the key cache by the amount specified here, then prefer the 138 # key cache method.  This is mainly used to force long character keys in
# large tables to use the slower key cache method to create the index. 140 myisam_sort_buffer_size=35M 141 
# Size of the Key Buffer, used to cache index blocks for MyISAM tables. 143 # Do not set it larger than 30% of your available memory, as some memory 144 # is also required by the OS to cache rows. Even if you're not using
# MyISAM tables, you should still set it to 8-64M as it will also be 146 # used for internal temporary disk tables. 147 key_buffer_size=23M 148 
# Size of the buffer used for doing full table scans of MyISAM tables. 150 # Allocated per thread, if a full scan is needed. 151 read_buffer_size=64K 152 read_rnd_buffer_size=256K 153 
# This buffer is allocated when MySQL needs to rebuild the index in
# REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE 156 # into an empty table. It is allocated per thread so be careful with 157 # large settings. 158 sort_buffer_size=256K 159 

#*** INNODB Specific options ***


# Use this option if you have a MySQL server with InnoDB support enabled 165 # but you do not plan to use it. This will save memory and disk space 166 # and speed up some things. 167 #skip-innodb 168 
# Additional memory pool that is used by InnoDB to store metadata 170 # information.  If InnoDB requires more memory for this purpose it will 171 # start to allocate it from the OS.  As this is fast enough on most 172 # recent operating systems, you normally do not need to change this
# value. SHOW INNODB STATUS will display the current amount used. 174 innodb_additional_mem_pool_size=2M 175 
# If set to 1, InnoDB will flush (fsync) the transaction logs to the 177 # disk at each commit, which offers full ACID behavior. If you are 178 # willing to compromise this safety, and you are running small 179 # transactions, you may set this to 0 or 2 to reduce disk I/O to the 180 # logs. Value 0 means that the log is only written to the log file and 181 # the log file flushed to disk approximately once per second. Value 2
# means the log is written to the log file at each commit, but the log 183 # file is only flushed to disk approximately once per second. 184 innodb_flush_log_at_trx_commit=1

# The size of the buffer InnoDB uses for buffering log data. As soon as
# it is full, InnoDB will have to flush it to disk. As it is flushed 188 # once per second anyway, it does not make sense to have it very large 189 # (even with long transactions). 190 innodb_log_buffer_size=1M 191 
# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and 193 # row data. The bigger you set this the less disk I/O is needed to 194 # access data in tables. On a dedicated database server you may set this
# parameter up to 80% of the machine physical memory size. Do not set it 196 # too large, though, because competition of the physical memory may 197 # cause paging in the operating system. Note that on 32bit systems you 198 # might be limited to 2-3.5G of user level memory per process, so do not 199 # set it too high. 200 innodb_buffer_pool_size=42M 201 
# Size of each log file in a log group. You should set the combined size 203 # of log files to about 25%-100% of your buffer pool size to avoid 204 # unneeded buffer pool flush activity on log file overwrite. However, 205 # note that a larger logfile size will increase the time needed for the 206 # recovery process. 207 innodb_log_file_size=10M 208 
# Number of threads allowed inside the InnoDB kernel. The optimal value 210 # depends highly on the application, hardware as well as the OS 211 # scheduler properties. A too high value may lead to thread thrashing. 212 innodb_thread_concurrency=10

 

 

三、my.ini 的配置参数说明

　　1、客户端参数

# CLIENT SECTION  2 # ----------------------------------------------------------------------
#  4 # The following options will be read by MySQL client applications.  5 # Note that only client applications shipped by MySQL are guaranteed  6 # to read this section. If you want your own MySQL client program to  7 # honor these values, you need to specify it as an option during the  8 # MySQL client library initialization.  9 # 10 [client] 11 
port=3306

[mysql] 15 
default-character-set=utf8

 

　　　　上面显示的是客户端的参数，[client]和[mysql]都是客户端，下面是参数简介：

port参数表示的是MySQL数据库的端口，默认的端口是3306，如果你需要更改端口号的话，就可以通过在这里修改。

default-character-set参数是客户端默认的字符集，如果你希望它支持中文，可以设置成gbk或者utf8。

这里还有一个password参数，在这里设置了password参数的值就可以在登陆时不用输入密码直接进入

　　

　　2、服务器端参数

# SERVER SECTION  2 # ----------------------------------------------------------------------
#  4 # The following options will be read by the MySQL Server. Make sure that  5 # you have installed the server correctly (see above) so it reads this 
# file.  7 #  8 [mysqld]  9 
# The TCP/IP Port the MySQL Server will listen on 11 port=3306


#Path to installation directory. All paths are usually resolved relative to this. 15 basedir="D:/MySQL/MySQL Server 5.5/"

#Path to the database root 18 datadir="D:/MySQL_Data/MySQL Server 5.5/Data/"

# The default character set that will be used when a new schema or table is
# created and no character set is defined 22 character-set-server=utf8 23 
# The default storage engine that will be used when create new tables when 25 default-storage-engine=INNODB 26 
# Set the SQL mode to strict 28 sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

# The maximum amount of concurrent sessions the MySQL server will 31 # allow. One of these connections will be reserved for a user with 32 # SUPER privileges to allow the administrator to login even if the 33 # connection limit has been reached. 34 max_connections=100

# Query cache is used to cache SELECT results and later return them 37 # without actual executing the same query once again. Having the query 38 # cache enabled may result in significant speed improvements, if your 39 # have a lot of identical queries and rarely changing tables. See the 40 # "Qcache_lowmem_prunes" status variable to check if the current value 41 # is high enough for your load. 42 # Note: In case your tables change very often or if your queries are 43 # textually different every time, the query cache may result in a 44 # slowdown instead of a performance improvement. 45 query_cache_size=15M 46 
# The number of open tables for all threads. Increasing this value 48 # increases the number of file descriptors that mysqld requires. 49 # Therefore you have to make sure to set the amount of open files 50 # allowed to at least 4096 in the variable "open-files-limit" in
# section [mysqld_safe] 52 table_cache=256

# Maximum size for internal (in-memory) temporary tables. If a table 55 # grows larger than this value, it is automatically converted to disk 56 # based table This limitation is for a single table. There can be many 57 # of them. 58 tmp_table_size=18M 59 

# How many threads we should keep in a cache for reuse. When a client 62 # disconnects, the client's threads are put in the cache if there aren't 63 # more than thread_cache_size threads from before. This greatly reduces 64 # the amount of thread creations needed if you have a lot of new
# connections. (Normally this doesn't give a notable performance
# improvement if you have a good thread implementation.) 67 thread_cache_size=8

 

　　　　上面是服务器端参数，一下是参数的简介：

    1.port参数也是表示数据库的端口。

　　2.basedir参数表示MySQL的安装路径。

　　3.datadir参数表示MySQL数据文件的存储位置，也是数据库表的存放位置。

　　4.default-character-set参数表示默认的字符集，这个字符集是服务器端的。

　　5.default-storage-engine参数默认的存储引擎。

　　6.sql-mode参数表示SQL模式的参数，通过这个参数可以设置检验SQL语句的严格程度。

　　7.max_connections参数表示允许同时访问MySQL服务器的最大连接数，其中一个连接是保留的，留给管理员专用的。

　　8.query_cache_size参数表示查询时的缓存大小，缓存中可以存储以前通过select语句查询过的信息，再次查询时就可以直接从缓存中拿出信息。

　　9.table_cache参数表示所有进程打开表的总数。

　　10.tmp_table_size参数表示内存中临时表的总数。

　　11.thread_cache_size参数表示保留客户端线程的缓存。

　　12.myisam_max_sort_file_size参数表示MySQL重建索引时所允许的最大临时文件的大小。

　　13.myisam_sort_buffer_size参数表示重建索引时的缓存大小。

　　14.key_buffer_size参数表示关键词的缓存大小。

　　15.read_buffer_size参数表示MyISAM表全表扫描的缓存大小。

　　16.read_rnd_buffer_size参数表示将排序好的数据存入该缓存中。

　　17.sort_buffer_size参数表示用于排序的缓存大小

　　

　　3、MyISAM 存储引擎特有的选项

#*** MyISAM Specific options  2 
# The maximum size of the temporary file MySQL is allowed to use while
# recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE.  5 # If the file-size would be bigger than this, the index will be created  6 # through the key cache (which is slower).  7 myisam_max_sort_file_size=100G  8 
# If the temporary file used for fast index creation would be bigger 10 # than using the key cache by the amount specified here, then prefer the 11 # key cache method.  This is mainly used to force long character keys in
# large tables to use the slower key cache method to create the index. 13 myisam_sort_buffer_size=35M 14 
# Size of the Key Buffer, used to cache index blocks for MyISAM tables. 16 # Do not set it larger than 30% of your available memory, as some memory 17 # is also required by the OS to cache rows. Even if you're not using
# MyISAM tables, you should still set it to 8-64M as it will also be 19 # used for internal temporary disk tables. 20 key_buffer_size=23M 21 
# Size of the buffer used for doing full table scans of MyISAM tables. 23 # Allocated per thread, if a full scan is needed. 24 read_buffer_size=64K 25 read_rnd_buffer_size=256K 26 
# This buffer is allocated when MySQL needs to rebuild the index in
# REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE 29 # into an empty table. It is allocated per thread so be careful with 30 # large settings. 31 sort_buffer_size=256K

 

 

　　4、INNODB 引擎的特有选项

#*** INNODB Specific options ***


# Use this option if you have a MySQL server with InnoDB support enabled  5 # but you do not plan to use it. This will save memory and disk space  6 # and speed up some things.  7 #skip-innodb  8 
# Additional memory pool that is used by InnoDB to store metadata 10 # information.  If InnoDB requires more memory for this purpose it will 11 # start to allocate it from the OS.  As this is fast enough on most 12 # recent operating systems, you normally do not need to change this
# value. SHOW INNODB STATUS will display the current amount used. 14 innodb_additional_mem_pool_size=2M 15 
# If set to 1, InnoDB will flush (fsync) the transaction logs to the 17 # disk at each commit, which offers full ACID behavior. If you are 18 # willing to compromise this safety, and you are running small 19 # transactions, you may set this to 0 or 2 to reduce disk I/O to the 20 # logs. Value 0 means that the log is only written to the log file and 21 # the log file flushed to disk approximately once per second. Value 2
# means the log is written to the log file at each commit, but the log 23 # file is only flushed to disk approximately once per second. 24 innodb_flush_log_at_trx_commit=1

# The size of the buffer InnoDB uses for buffering log data. As soon as
# it is full, InnoDB will have to flush it to disk. As it is flushed 28 # once per second anyway, it does not make sense to have it very large 29 # (even with long transactions). 30 innodb_log_buffer_size=1M 31 
# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and 33 # row data. The bigger you set this the less disk I/O is needed to 34 # access data in tables. On a dedicated database server you may set this
# parameter up to 80% of the machine physical memory size. Do not set it 36 # too large, though, because competition of the physical memory may 37 # cause paging in the operating system. Note that on 32bit systems you 38 # might be limited to 2-3.5G of user level memory per process, so do not 39 # set it too high. 40 innodb_buffer_pool_size=42M 41 
# Size of each log file in a log group. You should set the combined size 43 # of log files to about 25%-100% of your buffer pool size to avoid 44 # unneeded buffer pool flush activity on log file overwrite. However, 45 # note that a larger logfile size will increase the time needed for the 46 # recovery process. 47 innodb_log_file_size=10M 48 
# Number of threads allowed inside the InnoDB kernel. The optimal value 50 # depends highly on the application, hardware as well as the OS 51 # scheduler properties. A too high value may lead to thread thrashing. 52 innodb_thread_concurrency=10

 

　　　　上面是InnoDB存储引擎使用的参数，一下是参数的简介：

    1.innodb_additional_mem_pool_size参数表示附加的内存池，用来存储InnoDB表的内容。

　　2.innodb_flush_log_at_trx_commit参数是设置提交日志的时机，若设置为1，InnoDB会在每次提交后将事务日志写到磁盘上。

　　3.innodb_log_buffer_size参数表示用来存储日志数据的缓存区的大小。

　　4.innodb_buffer_pool_size参数表示缓存的大小，InnoDB使用一个缓冲池类保存索引和原始数据。

　　5.innodb_log_file_size参数表示日志文件的大小。

　　6.innodb_thread_concurrency参数表示在InnoDB存储引擎允许的线程最大数。 

　　

 

 

四、Linux 下的配置文件

 

五、

　　推荐阅读：

　　　　MySQL 配置文件详解

　　　　　MySQL my.cnf 参数配置优化详解

　　　　MySQL InnoDB 存储引擎参数优化