MySQL eats 100% CPU on a quad CPU system...
Hello people, I'm currently configuring a quad CPU system as a standalone MySQL server. The machine runs nothing except for MySQL and some trivial things like SSH and iptables. A second server acts as a webserver and is connected to this one though an internal LAN connection. Using top or ps, it shows that MySQL eats over 99% of all the available CPU. Using slmon, it shows that indeed all 4 CPUs are fully in use. Still, it appears to be terribly slow and I don't think MySQL should eat over 99% CPU on a quad CPU system... The machine runs mysqld 4.0.18 on Debian Sarge. A stripped down my.cnf is included below (I merely removed the comments). Could anyone tell me what can cause this problem? Thanks, - Fahr ===my.cnf=== [client] port= 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] err-log = /var/log/mysql/mysql.err socket = /var/run/mysqld/mysqld.sock open_files_limit = 8192 [mysqld] 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 language= /usr/share/mysql/english skip-locking thread_stack= 128K skip-innodb max_connections = 500 key_buffer = 150M myisam_sort_buffer_size = 64M join_buffer_size = 1M read_buffer_size = 1M sort_buffer_size = 1M table_cache = 1500 thread_cache_size = 128 wait_timeout = 14400 connect_timeout = 10 max_allowed_packet = 16M max_connect_errors = 10 query_cache_limit = 1M query_cache_size = 32M query_cache_type = 1 [mysqldump] quick max_allowed_packet = 16M [mysql] [isamchk] key_buffer = 64M sort_buffer = 64M read_buffer = 16M write_buffer = 16M -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: MySQL eats 100% CPU on a quad CPU system...
It depends on lots of things. But as an estimate.. Probably you need to add some indexes.. Which type of queries you are using? which database type? Other things.. what about database size? maybe you need more RAM etc.. Best Regards, Cemal Dalar a.k.a Jimmy System Administrator Web Developer http://www.dalar.net - Original Message - From: Fahr o Mavastradioz [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, August 16, 2004 3:48 PM Subject: MySQL eats 100% CPU on a quad CPU system... Hello people, I'm currently configuring a quad CPU system as a standalone MySQL server. The machine runs nothing except for MySQL and some trivial things like SSH and iptables. A second server acts as a webserver and is connected to this one though an internal LAN connection. Using top or ps, it shows that MySQL eats over 99% of all the available CPU. Using slmon, it shows that indeed all 4 CPUs are fully in use. Still, it appears to be terribly slow and I don't think MySQL should eat over 99% CPU on a quad CPU system... The machine runs mysqld 4.0.18 on Debian Sarge. A stripped down my.cnf is included below (I merely removed the comments). Could anyone tell me what can cause this problem? Thanks, - Fahr ===my.cnf=== [client] port= 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] err-log = /var/log/mysql/mysql.err socket = /var/run/mysqld/mysqld.sock open_files_limit = 8192 [mysqld] 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 language= /usr/share/mysql/english skip-locking thread_stack= 128K skip-innodb max_connections = 500 key_buffer = 150M myisam_sort_buffer_size = 64M join_buffer_size = 1M read_buffer_size = 1M sort_buffer_size = 1M table_cache = 1500 thread_cache_size = 128 wait_timeout = 14400 connect_timeout = 10 max_allowed_packet = 16M max_connect_errors = 10 query_cache_limit = 1M query_cache_size = 32M query_cache_type = 1 [mysqldump] quick max_allowed_packet = 16M [mysql] [isamchk] key_buffer = 64M sort_buffer = 64M read_buffer = 16M write_buffer = 16M -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: MySQL eats 100% CPU on a quad CPU system...
Are you swapping? Check vmstat and iostat Are your queries optimized, are they doing full table scans? Enable the slow query log. On Mon, 16 Aug 2004 14:48:35 +0200, Fahr o Mavastradioz [EMAIL PROTECTED] wrote: Hello people, I'm currently configuring a quad CPU system as a standalone MySQL server. The machine runs nothing except for MySQL and some trivial things like SSH and iptables. A second server acts as a webserver and is connected to this one though an internal LAN connection. Using top or ps, it shows that MySQL eats over 99% of all the available CPU. Using slmon, it shows that indeed all 4 CPUs are fully in use. Still, it appears to be terribly slow and I don't think MySQL should eat over 99% CPU on a quad CPU system... The machine runs mysqld 4.0.18 on Debian Sarge. A stripped down my.cnf is included below (I merely removed the comments). Could anyone tell me what can cause this problem? Thanks, - Fahr ===my.cnf=== [client] port= 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] err-log = /var/log/mysql/mysql.err socket = /var/run/mysqld/mysqld.sock open_files_limit = 8192 [mysqld] 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 language= /usr/share/mysql/english skip-locking thread_stack= 128K skip-innodb max_connections = 500 key_buffer = 150M myisam_sort_buffer_size = 64M join_buffer_size = 1M read_buffer_size = 1M sort_buffer_size = 1M table_cache = 1500 thread_cache_size = 128 wait_timeout = 14400 connect_timeout = 10 max_allowed_packet = 16M max_connect_errors = 10 query_cache_limit = 1M query_cache_size = 32M query_cache_type = 1 [mysqldump] quick max_allowed_packet = 16M [mysql] [isamchk] key_buffer = 64M sort_buffer = 64M read_buffer = 16M write_buffer = 16M -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
RE: MySQL eats 100% CPU on a quad CPU system...
I use memlock to ensure it stays in memory. More than likely it's table optimization. EXPLAIN and SHOW INDEXES will likely help you once you turn slow query logging on. -J -Original Message- From: Justin Swanhart [mailto:[EMAIL PROTECTED] Sent: Monday, August 16, 2004 3:24 PM To: [EMAIL PROTECTED] Subject: Re: MySQL eats 100% CPU on a quad CPU system... Are you swapping? Check vmstat and iostat Are your queries optimized, are they doing full table scans? Enable the slow query log. On Mon, 16 Aug 2004 14:48:35 +0200, Fahr o Mavastradioz [EMAIL PROTECTED] wrote: Hello people, I'm currently configuring a quad CPU system as a standalone MySQL server. The machine runs nothing except for MySQL and some trivial things like SSH and iptables. A second server acts as a webserver and is connected to this one though an internal LAN connection. Using top or ps, it shows that MySQL eats over 99% of all the available CPU. Using slmon, it shows that indeed all 4 CPUs are fully in use. Still, it appears to be terribly slow and I don't think MySQL should eat over 99% CPU on a quad CPU system... The machine runs mysqld 4.0.18 on Debian Sarge. A stripped down my.cnf is included below (I merely removed the comments). Could anyone tell me what can cause this problem? Thanks, - Fahr ===my.cnf=== [client] port= 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] err-log = /var/log/mysql/mysql.err socket = /var/run/mysqld/mysqld.sock open_files_limit = 8192 [mysqld] 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 language= /usr/share/mysql/english skip-locking thread_stack= 128K skip-innodb max_connections = 500 key_buffer = 150M myisam_sort_buffer_size = 64M join_buffer_size = 1M read_buffer_size = 1M sort_buffer_size = 1M table_cache = 1500 thread_cache_size = 128 wait_timeout = 14400 connect_timeout = 10 max_allowed_packet = 16M max_connect_errors = 10 query_cache_limit = 1M query_cache_size = 32M query_cache_type = 1 [mysqldump] quick max_allowed_packet = 16M [mysql] [isamchk] key_buffer = 64M sort_buffer = 64M read_buffer = 16M write_buffer = 16M -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
