问题
I am kind of hoping that someone might be able to offer some assistance with optimizing a my.cnf file for an extremely high volume mysql database server.
Our architecture is as follows:
Memory : 96GB
CPUs : 12
OS & Mysql : 64-bit
Disk Space : 1.2 TB
DB Engine : MyISAM
Our web application is used by roughly 300 client simultaneously. We need our my.cnf tuned to give the best possible performance for this infrastructure.
I am fully aware that indexes and optimized queries are a major factor in this, but we would like to start with a system that is configured properly and then follow that up with systematically re-engineering our queries accordingly.
Here is our current my.cnf file content:
[mysqld]
datadir=/home/mysql
socket=/home/mysql/mysql.sock
user=mysql
log-bin=mysql-bin
server-id=1
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=1
log-slow-queries = /var/log/mysqld_slow_queries.log
long_query_time = 10
max_connections = 500
key_buffer_size = 32768M
#max_allowed_packet = 2M
#table_open_cache = 128
#sort_buffer_size = 1024K
#net_buffer_length = 64K
#read_buffer_size = 1024K
#read_rnd_buffer_size = 1024K
#myisam_sort_buffer_size = 8M
query_cache_size = 128M
query_cache_limit = 128M
interactive_timeout = 300
wait_timeout = 300
# Added values after load testing
thread_cache_size = 8
#tmp_table_size = 256M
#max_heap_table_size = 256M
#table_cache = 512
#join_buffer_size = 512
log-error=/var/log/mysqld.log
innodb_buffer_pool_size=128M
#innodb_file_per_table
#innodb_log_file_size=250M
##innodb_buffer_pool_size=64M
#innodb_buffer_pool_size=1024M
#innodb_log_buffer_size=4M
##log-bin=mysql-bin
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
#[myisamchk]
#key_buffer = 64M
#sort_buffer = 64M
#read_buffer = 16M
#write_buffer = 16M
Any suggestions? Thanks folks.
Edit by RolandoMySQLDBA
Since all you data is MyISAM, please run this query and show the output
SELECT CONCAT(ROUND(KBS/POWER(1024,
IF(PowerOf1024<0,0,IF(PowerOf1024>3,0,PowerOf1024)))+0.4999),
SUBSTR(' KMG',IF(PowerOf1024<0,0,
IF(PowerOf1024>3,0,PowerOf1024))+1,1))
recommended_key_buffer_size FROM
(SELECT LEAST(POWER(2,32),KBS1) KBS
FROM (SELECT SUM(index_length) KBS1
FROM information_schema.tables
WHERE engine='MyISAM' AND
table_schema NOT IN ('information_schema','mysql')) AA ) A,
(SELECT 3 PowerOf1024) B;
@ Rolando - Thanks...the results of that query was 4G.
回答1:
Try starting with the Percona wizard and comparing their recommendations against your current settings one by one. Don't worry there aren't as many applicable settings as you might think.
https://tools.percona.com/wizard
Everyone points to key_buffer_size
first which you have addressed. With 96GB memory I'd be wary of any tiny default value (likely to be only 96M!).
回答2:
I tried this tool and it gave me good results.
https://github.com/major/MySQLTuner-perl
来源:https://stackoverflow.com/questions/10905226/mysql-my-cnf-performance-tuning-recommendations