Re: run in queue (Solaris)

The r field in vmstat is the count of processes that are currently runnable. However, depending on the platform specific implementation, this may or may not include
the number of jobs running on the CPU(s).Example - SunOS 4.1(and most BSD implementations)
include both the number of jobs running on the CPUs and those waiting in the queue. Solaris on the
other hand excludes the running jobs.
Say you have 5 runnable jobs on a 2way box : - running SunOS 4.1 : the r column shows 5 - running Solaris : the r column shows 3

The r column is a very good indicator if the machine is CPU bound. If you constantly having 5 runnable jobs
on a 2 way box, adding 3 CPU will prove very valiable and should boost performance. However - having
constantly 2 runnable jobs on a 12way box is a waste of money ... 2 CPU's would have been sufficient.
Typically, a runqueue of 3 to 4 times the number of CPU's will bring your machine to a crawl because the CPUs
are forced to jump between the runnable jobs. In your case a runqueu of 30 is a lot if you only have 4 CPU's - but ok if you 24CPUs...

A great book on this matter (besides 'The design of the Unix operating system') is "Optimizing Unix for Performance" by Amir H. Majidimehr.
http://www.amazon.com/exec/obidos/ASIN/0131115510/qid=1000763299/sr=2-2/ref= aps_sr_b_1_2/002-2667980-3793602

Cheers
Koert

"Jens" <superglad7_at_hotmail.com> wrote in message news:TWtp7.5603$sn6.611353_at_newsc.telia.net...
> Hi all
>
> This question should maybe go to a Solaris newsgroup but i´ve hope some
> DBA´s out there could answer this one pretty quick and easy..
> To the question:
>
> When running a "vmstat" on my Solaris 8 i could see a lot of "run in
queue",
> about 30 or
> more!
>
> I´ve searched for processes and found one process containing a suspect
query
> to the Oracle database wich contained a lot of wildcards and so on wich
i´ve
> simply killed.
> Afer this the system answered much faster.
>
> But, now to my question, what exact does "run in queue" tell me..?
> After killing the process the "run in queue" wasen´t down to zero
> immediately but slow decreasing.
> Now, after alomst 30 minutes the run in queue is down to about 3 or so and
> soon to be zero if i´ve know the system right..
> Is this what i´ve should expect or more exactly, coul´d someone please
tell
> me a bit more about "run in queue" and what this really means..?
> Regards
> Jens
>
>
>
>
Received on Mon Sep 17 2001 - 16:55:17 CDT