I'm trying to investigate I/O load my my Linux box (Centos6). I'm using
iotop, and the top lines look like this:
PID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND 376 be/3 root 0.00 B 4.26 M 0.00 % 32.79 % [jbd2/vda1-8] 1831 be/4 mysql 624.00 K 624.79 M 0.00 % 3.77 % mysqld ... 375 be/4 root 0.00 B 8.25 M 0.00 % 0.75 % [flush-252:0]
It seems that ext4 journalling process (jbd2) takes the majority of the blame. Is it normal? I'm looking at the accumulating statistics, and it just doesn't make any sense to me (e.g. disk write versus IO%). Is there any other tool like
iotop that I can use to look into disk activity on Linux?