Re: Scheduler fails to allow for "niceness" with new/fast processes

[Arjan van de Ven <arjan@infradead.org>]

On Tue, 16 Jun 2009 10:23:59 -0400
Robert Bradbury <robert.bradbury@gmail.com> wrote:

> I primarily use my system (Gentoo) for 3 tasks: (a) Browsing the web
> related to biomedical research (I may often have dozens of windows and
> hundreds of tabs open in several browsers); (b) Running fairly CPU &
> Disk I/O intensive genetics programs; (c) Performing low priority
> rebuilds of various packages (Gentoo packages, firefox/chrome
> releases, etc.
> 
> Now (a) is my top priority -- I want my active browser to get all of
> the CPU if it requires it (fast window/tab opens, quick page reloads &
> redraws, etc.);  (b) is of lesser priority and (c) is lowest priority.
>  This is on a 2.8 GHz Pentium IV (Prescott) with 3GB of RAM and 12GB
> of swap on two drives.
> 
> Now I normally run (c) processes at nice -n 19 to (in theory) get the
> least CPU allocation.  But it would appear that this does not work.  I
> often experience extremely poor user (esp. browser) performance when
> running package builds.  In monitoring the package builds I find that


have you tried running latencytop in this workload to see why you're
really stalling? Latencytop can at least tell you for sure if it's
a scheduler issue or something else...

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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