mysqld causes high CPU load
- by Radu
My mysqld goes to use 99.9% of CPU for variable time (between 2 - 20 minutes), and then goes back to normal 0.1% - 5%.
Checked processlist: all is normal, 1 to 20 inserts or updates that last 2 to 5 sec, and about 20 process that are in Sleep Mode (maybe because the scripts don't close the mysql connection, but are they are closed in about 5 - 10 secs, I didn't make the scripts :P but the server was running fine the last 2 years, since is was made):
| 15375 | root | localhost | stoc | Query | 0 | NULL | show processlist |
| 79480 | pppoe | localhost | pppoe | Sleep | 4 | NULL | NULL |
| 79481 | pppoe | localhost | pppoe | Sleep | 4 | NULL | NULL |
| 79482 | pppoe | localhost | pppoe | Sleep | 4 | NULL | NULL |
| 79483 | pppoe | localhost | pppoe | Query | 0 | init | UPDATE acc SET InputOctets="0", OutputOctets="0", InputPackets="unknown", OutputPackets="User |
| 79484 | pppoe | localhost | pppoe | Sleep | 5 | NULL | NULL |
| 79485 | pppoe | localhost | pppoe | Sleep | 5 | NULL | NULL |
| 79486 | pppoe | localhost | pppoe | Sleep | 5 | NULL | NULL
Checked raid, seemns OK:
[root@db2]# cat /proc/mdstat
Personalities : [raid5] [raid4] [raid1]
md0 : active raid1 sdd1[3] sdc1[2] sdb1[0] sda1[1]
136448 blocks [4/4] [UUUU]
md1 : active raid5 sdd2[3] sdc2[2] sdb2[0] sda2[1]
12023808 blocks level 5, 256k chunk, algorithm 2 [4/4] [UUUU]
md3 : active raid5 sda4[1] sdd4[3] sdc4[2] sdb4[0]
203647488 blocks level 5, 256k chunk, algorithm 2 [4/4] [UUUU]
md2 : active raid5 sda3[1] sdd3[3] sdc3[2] sdb3[0]
24024576 blocks level 5, 256k chunk, algorithm 2 [4/4] [UUUU]
unused devices: <none>
[root@db2]#
top sees my mysqld cpu load, but nothing else seems to be wrong:
[root@db2]# top
top - 17:56:05 up 7 days, 3:55, 3 users, load average: 32.93, 24.72, 22.70
Tasks: 75 total, 4 running, 71 sleeping, 0 stopped, 0 zombie
Cpu(s): 63.4% us, 36.6% sy, 0.0% ni, 0.0% id, 0.0% wa, 0.0% hi, 0.0% si, 0.0% st
Mem: 1988824k total, 1304776k used, 684048k free, 99588k buffers
Swap: 12023800k total, 0k used, 12023800k free, 951028k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
5754 mysql 19 0 236m 57m 5108 R 99.9 2.9 21:58.76 mysqld
1 root 16 0 7216 700 580 S 0.0 0.0 0:00.39 init
2 root RT 0 0 0 0 S 0.0 0.0 0:00.00 migration/0
Repaired all mysql databases, reindexed raid ... I'm running out of ideeas ...
Anyone has an ideea what can go wrong with this server ?
Thank you