MySQL Extremely High Disk Activity (Read Operations)
- by Jake Schoermer
I have 1GB Linode VPS with a standard LAMP stack. Apache is tuned fine but for some reason MySQL's disk usage is high. This is causing really slow site load times. RAM and CPU usage are fine.
Can anyone give me any pointers on tuning mysql's disk performance? I'm using InnoDB. iotop output is below.
Total DISK READ: 38.50 M/s | Total DISK WRITE: 27.20 K/s
TID PRIO USER DISK READ> DISK WRITE SWAPIN IO COMMAND
9808 be/4 mysql 22.40 M/s 0.00 B/s 0.00 % 63.75 % mysqld
10045 be/4 mysql 2.06 M/s 0.00 B/s 0.00 % 26.65 % mysqld
9987 be/4 mysql 1694.38 K/s 0.00 B/s 0.00 % 18.33 % mysqld
10015 be/4 mysql 1554.47 K/s 0.00 B/s 0.00 % 12.71 % mysqld
10019 be/4 mysql 1461.21 K/s 0.00 B/s 0.00 % 5.58 % mysqld
9839 be/4 mysql 1383.48 K/s 0.00 B/s 0.00 % 25.69 % mysqld
10031 be/4 mysql 1243.58 K/s 0.00 B/s 0.00 % 5.68 % mysqld
10023 be/4 mysql 1057.04 K/s 0.00 B/s 0.00 % 2.02 % mysqld
10020 be/4 mysql 1025.95 K/s 0.00 B/s 0.00 % 7.05 % mysqld
10001 be/4 mysql 808.33 K/s 683.97 K/s 0.00 % 1.16 % mysqld
10025 be/4 mysql 746.15 K/s 0.00 B/s 0.00 % 3.28 % mysqld
10043 be/4 mysql 715.06 K/s 0.00 B/s 0.00 % 0.48 % mysqld
10044 be/4 mysql 672.31 K/s 0.00 B/s 0.00 % 5.25 % mysqld
10034 be/4 mysql 668.42 K/s 1989.73 K/s 0.00 % 5.31 % mysqld
9985 be/4 mysql 450.80 K/s 124.36 K/s 0.00 % 8.83 % mysqld
9989 be/4 mysql 357.53 K/s 0.00 B/s 0.00 % 5.21 % mysqld
10033 be/4 mysql 186.54 K/s 0.00 B/s 0.00 % 1.59 % mysqld
10021 be/4 mysql 155.45 K/s 435.25 K/s 0.00 % 1.23 % mysqld
10007 be/4 mysql 124.36 K/s 0.00 B/s 0.00 % 0.53 % mysqld
9763 be/4 www-data 38.86 K/s 0.00 B/s 0.00 % 4.56 % apache2 -k start
10027 be/4 mysql 31.09 K/s 0.00 B/s 0.00 % 4.24 % mysqld
1 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % init
2 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kthreadd]
3 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [ksoftirqd/0]
4 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kworker/0:0]
5 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kworker/u:0]
6 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [migration/0]
7 rt/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [migration/1]