Why doesn't my IOstat change its output at all?

Question

My IOstat doesn't change...at all. It'll show a change in blocks being read and written, but it doesn't change at all when it comes to blocks/kB/MB read and written. When the server sits idle...it shows 363kB_read/s, 537kB_wrtn/s.

If I put it under heavy load...it says the same thing. Is it bugged out? How do I fix it?

Using Centos 6, being used a primary mysql server.

score 5 · Accepted Answer · answered Mar 18 '15 at 18:16

5

Could you list the specific command you are using?

The first printout is usually the average over the life of the system it rarely changes.

Run "iostat -x 1 10" that will get you 10 runs of iostat in 1 second intervals with extended statistics. run 2 - 10 should have the data you want. If it does then you can fiddle with the parameters to get exactly what you need.

answered Mar 18 '15 at 18:16

user107143

74
2

This worked. I don't know why, but when I initially would just use "iostat -k" it would give me the SAME readout. Every. Single. Time. This at least shows me some changing, albeit small variation. Thanks for the help. – Sqenix Mar 18 '15 at 18:31

score 1 · Answer 2 · answered Feb 09 '23 at 23:36

Its because iostat run once only shows stats since last reboot. To get current stats you have to run it n seconds apart, 2 or more times. This example runs it 2 times and only shows you the second output, which is recent statistics

iostat -k 1 2 |tail -20

Why doesn't my IOstat change its output at all?

2 Answers2