MySql配置（网易的）

Hompy项目现使用2台数据服务器，主从数据库内存分别为8G和6G。
开始老是down机，以my-huge为基础配了很多次，都不行，
后来，借用了mail.sanook.com的配置，撑了一断时间，还是不理想。
再借用网易(163.com)一个子项目的my.cnf试了一下，几个月没down，先用它撑一下。
注：网易使用的是2G内存的。

共享一下：
# Example MySQL config file for very large systems.
#
# This is for a large system with memory of 1G-2G where the system runs mainly
# MySQL.
#
# 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          = /var/lib/mysql/mysql.sock

# Here follows entries for some specific programs

# The MySQL server
[mysqld]

port            = 3306
socket          = /var/lib/mysql/mysql.sock
skip-locking
skip-innodb
skip-bdb

#back_log=100
back_log=200

#key_buffer=500M
key_buffer=512M

#key_buffer = 384M
#max_allowed_packet = 2M
#max_allowed_packet = 1M
max_allowed_packet = 4M

#table_cache = 512
table_cache = 1024

#sort_buffer_size=32M
#sort_buffer_size = 2M
sort_buffer_size = 16M

#read_buffer_size = 8M
#read_buffer_size = 2M
read_buffer_size = 16M

#read_rnd_buffer_size = 16M
#read_rnd_buffer_size = 8M
read_rnd_buffer_size = 32M

#myisam_sort_buffer_size = 256M
myisam_sort_buffer_size = 64M
#thread_cache =80
thread_cache = 8
#query_cache_size = 64M
#query_cache_size = 32M
query_cache_size = 16M

log-slow-queries=/var/log/slowlog.log
long_query_time = 2
# Try number of CPU's*2 for thread_concurrency
thread_concurrency = 4
default-character-set=utf8
### mysql tuning
#set-variable = max_user_connections=600
set-variable = max_user_connections=1000

set-variable = max_connections=1000

#set-variable = table_cache=1200
#set-variable = max_allowed_packet=1M

#set-variable = max_connect_errors=999999
#set-variable = max_connect_errors=20
set-variable = max_connect_errors=1000

set-variable = wait_timeout=10
#set-variable = interactive_timeout=300
set-variable = interactive_timeout=120

#set-variable = tmp_table_size = 2M
#set-variable = join_buffer_size = 2M
###

# 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 = /var/log/mysql/mysql-bin.log
# binlog-do-db = exampledb

# 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=<host>, MASTER_PORT=<port>,
#    MASTER_USER=<user>, MASTER_PASSWORD=<password> ;
#
#    where you replace <host>, <user>, <password> by quoted strings and
#    <port> 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     =   <hostname>
#
# The username the slave will use for authentication when connecting
# to the master - required
#master-user     =   <username>
#
# The password the slave will authenticate with when connecting to
# the master - required
#master-password =   <password>
#
# The port the master is listening on.
# optional - defaults to 3306
#master-port     =  <port>
#
# binary logging - not required for slaves, but recommended
log-bin
binlog-do-db = hompy_mweb

# Point the following paths to different dedicated disks
#tmpdir         = /tmp/
tmpdir         = /var/mysqltmp
#log-update     = /path-to-dedicated-directory/hostname

# Uncomment the following if you are using BDB tables
#bdb_cache_size = 384M
#bdb_max_lock = 100000

# Uncomment the following if you are using InnoDB tables
#innodb_data_home_dir = /var/lib/mysql/
#innodb_data_file_path = ibdata1:2000M;ibdata2:10M: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 = 384M
#innodb_additional_mem_pool_size = 20M
# Set .._log_file_size to 25 % of buffer pool size
#innodb_log_file_size = 100M
#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
default-character-set=utf8
[isamchk]
key_buffer = 256M
sort_buffer_size = 256M
read_buffer = 2M
write_buffer = 2M

[isamchk]
key_buffer = 256M
sort_buffer_size = 256M
read_buffer = 2M
write_buffer = 2M

[myisamchk]
key_buffer = 256M
sort_buffer_size = 256M
read_buffer = 2M
write_buffer = 2M

[mysqlhotcopy]
interactive-timeout

在mysql安装之后，有范例的配置文件。
windows下就在安装目录。

linux可能在/usr/share/mysql/下
比如my-innodb-heavy-4G.cnf 文件。

可以copy这些范本，然后修改修改。

因此投票新手帖……不好意思。

这个网易的配置文件太保守了，2G内存的数据库服务器，很显然query_cache开得太小。还有很多参数都不太适用，例如他关闭innodb，仅仅使用myisam，想必他是一个大量只读的数据库。对于没有一个相应的应用场景来说，这种配置毫无意义。

至于你的宕机问题，很可能是你原来的配置不合适导致的，但是可以肯定的是这个配置也很可能不适合你。

只是作为前期使用的参考而已，呵。
在数据量大的时候肯定要改的。

正要向你们学习。
可以给我一个8G内存使用的my.cnf的参考吗？
非常谢谢!

顺祝：元旦快乐！

http://mysqldatabaseadministration.blogspot.com/2005/11/mysql-5-optimization-and-tuning-guide.html
这篇文章值得一读。

另外，优化跟你的具体数据也有点关系。
有一个非常大的表，访问量也大的话，有的缓存就要设大一些。

非常感谢ls的dwangel和robbin!