disk wait mystery

[Brett Wynkoop]

On Wed, 30 Jan 2013 17:52:36 +0700
Erich Dollansky <erichsfreebsdlist at alogt.com> wrote:

> how I understand the system, I would say that these tasks are all
> swapped out to disk.
> 
> Erich


Probably not swapped out:


wynkoop at beaglebone:~ % pstat -s
Device          1K-blocks     Used    Avail Capacity
/dev/md0           788480      184   788296     0%
wynkoop at beaglebone:~ % 


I think Oliver must have hit upon the right answer, as I do see similar
results on my other FreeBSD boxes.  I just never really paid attention
to it as my other boxes are running many more things and are swapping. 

Thanks Oliver.

Too bad kernel threads that are busy show up as disk wait when no disk
i/o is involved.   Well in that fantasy land where I am a kernel hacker
(LOL) I guess I can code in a different code for non-disk based waits!

-Brett
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