Re: [gentoo-user] Re: Kon Colivas is working again on a new scheduler for Desktop/Multimedia/Gaming PCs

[Volker Armin Hemmann]

On Samstag 05 September 2009, Nikos Chantziaras wrote:
> On 09/05/2009 05:59 PM, Volker Armin Hemmann wrote:
> >> 1000 Hz timer freq
> >
> > change that to 300
> >
> >> Did you mean tickless system with "noticks"? I have this enabled ATM
> >
> > deactivate that.
>
> Even with that, there still are problems.  With composite enabled, move
> an mplayer window around and see how the video starts to skip big
> amounts of frames at the moment you start moving and when you "drop" it
> again.  The compositor takes away CPU time and mplayer starves for a
> short time.  BFS solves this.

nope. No drops. vlc, xine, mplayer. At least no visible drop - and none of the 
three is complaining. 

But there is a pro-tip: use a non-broken X. aka one with

fedora_dont_backfill_bg_none.patch

>
> Also, have you considered that you got it all backwards?  The kernel
> configuration tells you that for lower latencies, you should use 1000Hz
> and PREEMPT.  It even says "Desktop" right there.  Why should I take
> your word over that of the kernel devs who actually wrote that code?

low latency means bad throughput and that hurts IO.


>
> > if that does not help:
> >> And with extX I assume you meant the file systems? I'm aware that ext3
> >> is not very efficient with large files, but I can't/don't want to use
> >> ext4 yet because I need to access the partition from windows.
> >
> > neither use ext3 nor ext4.
>
> The I/O blockage has nothing to do with the CPU scheduler.  Or at least
> not much.  The "GUI freezes during file copy" problem is another beast.
>   BFS doesn't solve that.
>

it is a mixture of cpu-scheduler, 'harddisk'-scheduler, filesystem, drivers.