- A+
代码:
- # 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)
- #
- # You can copy this file to
- # /etc/my.cnf to set global options,
- # mysql-data-dir/my.cnf to set server-specific options (in this
- # installation this directory is /var/lib/mysql) or
- # ~/.my.cnf to set user-specific options.
- #
- # 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]
- #password = your_password
- port = 3306
- socket = /tmp/mysql.sock
- #socket = /var/lib/mysql/mysql.sock
- # Here follows entries for some specific programs
- # The MySQL server
- [mysqld]
- port = 3306
- socket = /tmp/mysql.sock
- #socket = /var/lib/mysql/mysql.sock
- skip-locking
- key_buffer = 128M
- max_allowed_packet = 1M
- table_cache = 256
- sort_buffer_size = 1M
- net_buffer_length = 16K
- myisam_sort_buffer_size = 1M
- max_connections=120
- #addnew config
- wait_timeout =120
- back_log=100
- read_buffer_size = 1M
- thread_cache=32
- skip-innodb
- skip-bdb
- skip-name-resolve
- join_buffer_size=512k
- query_cache_size = 32M
- interactive_timeout=120
- long_query_time=10
- log_slow_queries= /usr/local/mysql4/logs/slow_query.log
- query_cache_type= 1
- # Try number of CPU's*2 for thread_concurrency
- thread_concurrency = 4
- #end new config
- # Don'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
- # 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 = 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=, MASTER_PORT=,
- # MASTER_USER=, MASTER_PASSWORD= ;
- #
- # where you replace , , by quoted strings and
- # by the master's port number (3306 by default).
- #
- # Example:
- #
- # CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,
- # MASTER_USER='joe', MASTER_PASSWORD='secret';
- #
- # 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' 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 = 2
- #
- # The replication master for this slave - required
- #master-host =
- #
- # The username the slave will use for authentication when connecting
- # to the master - required
- #master-user =
- #
- # The password the slave will authenticate with when connecting to
- # the master - required
- #master-password =
- #
- # The port the master is listening on.
- # optional - defaults to 3306
- #master-port =
- #
- # binary logging - not required for slaves, but recommended
- #log-bin
- # Point the following paths to different dedicated disks
- #tmpdir = /tmp/
- #log-update = /path-to-dedicated-directory/hostname
- # Uncomment the following if you are using BDB tables
- #bdb_cache_size = 4M
- #bdb_max_lock = 10000
- # Uncomment the following if you are using InnoDB tables
- #innodb_data_home_dir = /var/lib/mysql/
- #innodb_data_file_path = ibdata1:10M:autoextend
- #innodb_log_group_home_dir = /var/lib/mysql/
- #innodb_log_arch_dir = /var/lib/mysql/
- # You can set .._buffer_pool_size up to 50 - 80 %
- # of RAM but beware of setting memory usage too high
- #innodb_buffer_pool_size = 16M
- #innodb_additional_mem_pool_size = 2M
- # Set .._log_file_size to 25 % of buffer pool size
- #innodb_log_file_size = 5M
- #innodb_log_buffer_size = 8M
- #innodb_flush_log_at_trx_commit = 1
- #innodb_lock_wait_timeout = 50
- [mysqldump]
- quick
- max_allowed_packet = 16M
- [mysql]
- no-auto-rehash
- # Remove the next comment character if you are not familiar with SQL
- #safe-updates
- [isamchk]
- key_buffer = 20M
- sort_buffer_size = 20M
- read_buffer = 2M
- write_buffer = 2M
- [myisamchk]
- key_buffer = 20M
- sort_buffer_size = 20M
- read_buffer = 2M
- write_buffer = 2M
- [mysqlhotcopy]
- interactive-timeout
补充:
优化table_cachetable_cache指定表高速缓存的大小。每当MySQL访问一个表时,如果在表缓冲区中还有空间,该表就被打开并放入其中,这样可以更快地访问表内容。通过检查峰值时间的状态值Open_tables和Opened_tables,可以决定是否需要增加 table_cache的值。如果你发现open_tables等于table_cache,并且opened_tables在不断增长,那么你就需要增加table_cache的值了(上述状态值可以使用SHOW STATUS LIKE ‘Open%tables'获得)。注意,不能盲目地把table_cache设置成很大的值。如果设置得太高,可能会造成文件描述符不足,从而造成性能不稳定或者连接失败。对于有1G内存的机器,推荐值是128-256。
案例1:该案例来自一个不是特别繁忙的服务器
table_cache – 512
open_tables – 103
opened_tables – 1273
uptime – 4021421 (measured in seconds)
该案例中table_cache似乎设置得太高了。在峰值时间,打开表的数目比table_cache要少得多。
案例2:该案例来自一台开发服务器。
table_cache – 64
open_tables – 64
opened-tables – 431
uptime – 1662790 (measured in seconds)
虽然open_tables已经等于table_cache,但是相对于服务器运行时间来说,opened_tables的值也非常低。因此,增加table_cache的值应该用处不大。
案例3:该案例来自一个upderperforming的服务器
table_cache – 64
open_tables – 64
opened_tables – 22423
uptime – 19538
该案例中table_cache设置得太低了。虽然运行时间不到6小时,open_tables达到了最大值,opened_tables的值也非常高。这样就需要增加table_cache的值。优化key_buffer_sizekey_buffer_size指定索引缓冲区的大小,它决定索引处理的速度,尤其是索引读的速度。通过检查状态值Key_read_requests和Key_reads,可以知道key_buffer_size 设置是否合理。比例key_reads / key_read_requests应该尽可能的低,至少是1:100,1:1000更好(上述状态值可以使用SHOW STATUS LIKE ‘key_read%'获得)。key_buffer_size只对MyISAM表起作用。即使你不使用MyISAM表,但是内部的临时磁盘表是 MyISAM表,也要使用该值。可以使用检查状态值created_tmp_disk_tables得知详情。对于1G内存的机器,如果不使用 MyISAM表,推荐值是16M(8-64M)。
案例1:健康状况
key_buffer_size – 402649088 (384M)
key_read_requests – 597579931
key_reads - 56188
案例2:警报状态
key_buffer_size – 16777216 (16M)
key_read_requests – 597579931
key_reads - 53832731
案例1中比例低于1:10000,是健康的情况;案例2中比例达到1:11,警报已经拉响。