You can use iostat to find out disk utilization, but with iotop you can monitor the actual read/write. iotop watches the I/O usage information output by the kernel and displays it in a table of current I/O usage by processes.
iotop syntax for monitoring I/O usage
- -o Will only show processes or threads which are actually doing I/O instead of showing all processes/threads.
- -a Will show accumulated I/O instead of bandwith. With this syntax iotop shows the amount of I/O processes have done since iotop started.
If the -a syntax doesn’t work you have to update iotop to the latest version by installing it manually.
Example:
TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
265 be/3 root 0.00 B 16.00 K 0.00 % 0.05 % [jbd2/sda5-8]
2567 be/4 root 0.00 B 23.73 M 0.00 % 0.00 % wget http://mirror.us.leaseweb.net/speedtest/50mb.bin
24908 be/4 www-data 0.00 B 4.00 K 0.00 % 0.00 % apache2 -k start
1955 be/4 www-data 0.00 B 16.00 K 0.00 % 0.00 % apache2 -k start
One Response
Monitoring IO on a system can be very tricky at times..Comparing the results provided by multiple tools, is a nice idea to reach a conclusion..
http://www.slashroot.in/linux-system-io-monitoring