Re: RSDL v0.31

[Con Kolivas <kernel@kolivas.org>]

On Saturday 17 March 2007 08:55, Al Boldi wrote:
> Con Kolivas wrote:
> > Here are full patches for rsdl 0.31 for various base kernels. A full
> > announce with a fresh -mm series will follow...
> >
> > http://ck.kolivas.org/patches/staircase-deadline/2.6.20.3-rsdl-0.31.patch
>
> Thanks!  It looks much better now.

Thank you. You should find most of your latency concerns you brought up have 
been addressed by this change.

> With X nice'd at -10, and 11 hogs loading the cpu, interactivity looks good
> until the default timeslice/quota is exhausted and slows down.  Maybe
> adjusting this according to nice could help.

Not sure what you mean by that. It's still a fair distribution system, it's 
just that nice -10 has quite a bit more cpu allocated than nice 0. Eventually 
if you throw enough load at it it will slow down too.

> It may also be advisable to fix latencies according to nice, and adjust
> timeslices instead.  This may help scaleability a lot, as there are some
> timing sensitive apps that may crash under high load.

You will find that is the case already with this version. Even under heavy 
load if you were to be running one server niced (say httpd nice 19 in the 
presence of mysql nice 0) the latencies would be drastically reduced compared 
to mainline behaviour. I am aware this becomes an issue for some heavily 
loaded servers because some servers run multithreaded while others do not, 
forcing the admins to nice their multithreaded ones. 

> Thanks!
>
> --
> Al

-- 
-ck