Linux : Hisk disk io

Subliminal Aura · 18 Sep 2007 at 17:49

Anyone know how I find out which process is causing the most disk io ?

Subliminal Aura · 18 Sep 2007 at 17:55

Hisk disk io ?

Sorry for the repost, I posted in the wrong forum... :rolleyes:

The question I am pondering over is ..

Anyone know how I find out which process is causing the most disk io ?

Subliminal Aura · 18 Sep 2007 at 18:05

for what its worth : iotop needs kernel >= 2.6.20 http://guichaz.free.fr/misc/

any alternatives ?

robmiller · 18 Sep 2007 at 18:07

http://www.microsoft.com/technet/sysinternals/Utilities/ProcessExplorer.mspx

Choose the "IO History" column to see a nice realtime graph of IO usage for each process.

Edit: Curses, Linux. AFAIK it's not possible to get per-process data—not with a stock kernel anyway—but I'm sure someone will be along to correct me. You can get per-device disk usage stats with `iostat`.

NicNac · 18 Sep 2007 at 18:14

I'd give the chaps over at linuxquestions a shout maybe they will be able to help you with this one

Una · 18 Sep 2007 at 18:52

robmiller said:
http://www.microsoft.com/technet/sysinternals/Utilities/ProcessExplorer.mspx

Choose the "IO History" column to see a nice realtime graph of IO usage for each process.

Yes because microsoft tools work on Linux!..

You can look at the wa column in 'top' output to see the wait. Read the man pages for iostat and lsof, and between those two tools you should be able to work it out.

Una · 18 Sep 2007 at 19:11

See my post in the other section..

psyr33n · 18 Sep 2007 at 20:57

Edit: Posted a link to the right forum, didn't notice you'd already posted it there too.

Subliminal Aura · 19 Sep 2007 at 10:23

psyr33n said:
Edit: Posted a link to the right forum, didn't notice you'd already posted it there too.

Huh ? I don't get :\

I just posted this here and in HTML questions by mistake :eek:

Anyway I'm trying to hunt down the issue by using sar its not pretty... linuxquestions seem to not have anything that I dont know already without the need to change my kernel... :rolleyes:

Dj_Jestar · 19 Sep 2007 at 10:44

have a read of the vmstat man pages, particularly for options -d -D and -p.

Subliminal Aura · 19 Sep 2007 at 10:50

Dj_Jestar said:
have a read of the vmstat man pages, particularly for options -d -D and -p.

Process stats doooooood not global. :mad:

Subliminal Aura · 19 Sep 2007 at 10:55

The closest I've got is by using :

sar -b -r -x ALL -d 1 1

but can't see the process that is causing the disk io...

but in fairness I got the feeling that it might be a process that forks and dies too rapidly for it to be noticed.