以下为自己线上服务器my.cnf的配置，大家可以参考一下：

服务器配置：ubuntu 8核 8G内存

mysql版本: mysql-5.5

[client]

default-character-set=utf8

port = 3306

socket = /var/run/mysqld/mysqld.sock

[mysqld_safe]

socket = /var/run/mysqld/mysqld.sock

nice = 0

[mysqld]

character-set-server=utf8

init_connect='SET NAMES utf8'

max_connections=1500

max_connect_errors = 6000

#wait_timeout=31536000

#interactive_timeout=31536000

wait_timeout=300

interactive_timeout=300

skip-external-locking

skip-name-resolve

skip-host-cache

log-slow-queries=/var/lib/mysql/slowquery.log

long_query_time=2

thread_concurrency = 16

concurrent_insert = 2

innodb_additional_mem_pool_size = 16M

innodb_buffer_pool_size = 4G

innodb_data_file_path = ibdata1:1G:autoextend

innodb_log_buffer_size = 16M

innodb_log_file_size = 128M

innodb_log_files_in_group = 2

innodb_lock_wait_timeout=120

innodb_thread_concurrency = 16

innodb_file_io_threads = 4

innodb_flush_log_at_trx_commit = 2

innodb_log_files_in_group = 3

innodb_max_dirty_pages_pct = 90

innodb_file_per_table = 0

transaction_isolation = READ-COMMITTED

back_log = 600

open_files_limit = 10240

table_cache = 614

max_heap_table_size = 256M

tmp_table_size = 256M

sort_buffer_size = 2M

join_buffer_size = 2M

read_buffer_size = 1M

read_rnd_buffer_size = 16M

bulk_insert_buffer_size = 64M

key_buffer_size = 128M

user = mysql

pid-file = /var/run/mysqld/mysqld.pid

socket = /var/run/mysqld/mysqld.sock

port = 3306

basedir = /usr

datadir = /var/lib/mysql

tmpdir = /tmp

lc-messages-dir = /usr/share/mysql

max_allowed_packet = 32M

thread_stack = 192K

thread_cache_size = 300

myisam-recover = BACKUP

query_cache_limit = 4M

query_cache_min_res_unit = 2k

#query_cache_size = 64M

query_cache_size = 0M

log_error = /var/log/mysql/error.log

binlog_cache_size = 4M

max_binlog_cache_size = 8M

expire_logs_days = 7

max_binlog_size = 200M

[mysqldump]

quick

quote-names

max_allowed_packet = 32M

[mysql]

[isamchk]

key_buffer = 16M

!includedir /etc/mysql/conf.d/