mysql using >100% cpu

[bdj]

I'm running freebsd 6.1
dual core 2,33 ghz 4mb cache, 2gb RAM

For some reason mysql is using more than 100% cpu, is something wrong?




last pid: 12809; load averages: 6.90, 5.38, 4.96 up 37+04:21:30 22:26:20
199 processes: 6 running, 193 sleeping
CPU states: 32.5% user, 0.0% nice, 67.1% system, 0.4% interrupt, 0.0% idle
Mem: 752M Active, 332M Inact, 247M Wired, 69M Cache, 112M Buf, 600M Free
Swap: 4068M Total, 4068M Free

PID USERNAME THR PRI NICE SIZE RES STATE C TIME CPU COMMAND
12483 mysql 69 20 0 453M 84336K kserel 0 23:25 136.67% mysqld
12803 apache 1 20 0 36968K 30544K lockf 1 0:00 0.73% httpd
12741 apache 1 20 0 35808K 29352K lockf 1 0:00 0.39% httpd
763 root 1 8 0 852K 280K nanslp 0 0:58 0.00% da-popb4smtp
529 root 1 96 0 3640K 2088K select 1 0:38 0.00% sshd
94077 apache 1 4 0 37572K 30908K sbwait 1 0:30 0.00% httpd
95011 apache 1 4 0 37488K 30824K sbwait 0 0:29 0.00% httpd
93265 apache 1 4 0 37408K 30732K sbwait 0 0:29 0.00% httpd
96241 apache 1 4 0 37432K 30784K sbwait 0 0:28 0.00% httpd
94275 apache 1 4 0 37624K 30976K sbwait 1 0:28 0.00% httpd
94091 apache 1 4 0 37536K 30872K sbwait 0 0:28 0.00% httpd
94365 apache 1 4 0 37380K 30736K sbwait 1 0:28 0.00% httpd
94963 apache 1 4 0 37476K 30812K sbwait 0 0:28 0.00% httpd
95010 apache 1 4 0 37504K 30860K sbwait 1 0:28 0.00% httpd




i have thread_concurrency=4 in my.cnf

[Rich-Boy]

How much is MYSQL being accessed by users? Take a look at the processes list inside phpmyadmin or install mytop [/usr/ports/databases/mytop]
Chances are the problem is more complex than this but it's a start.

[bdj]

Hi,

thanks for the reply.

To inform other readers, i figured out that >100 cpu is possible. It's possible because of multi cores. Basicly 100% of the first core and the rest from the other core.

Second, i solved the problem but removing a large database which caused the massive cpu usage when more than 50 threads were connected.