Re: [PATCH] Preemption Latency Measurement Tool

Dieter Nützel
2001-09-22T23:46:24Z

Am Sonntag, 23. September 2001 01:40 schrieb safemode:
> ok. The preemption patch helps realtime applications in linux be a little
> more close to realtime. I understand that. But your mp3 player shouldn't
> need root permission or renicing or realtime priority flags to play mp3s.
> To test how well the latency patches are working you should be running
> things all at the same priority. The main issue people are having with
> skipping mp3s is not in the decoding of the mp3 or in the retrieving of the
> file, it's in the playing in the soundcard. That's being affected by
> dbench flooding the system with irq requests. I'm inclined to believe it's
> irq requests because the _only_ time i have problems with mp3s (and i dont
> change priority levels) is when A. i do a cdparanoia -Z -B "1-" or
> dbench 32. I bet if someone did these tests on scsi hardware with the
> latency patch, they'd find much better results than us users of ide
> devices.

Nope.
If you would have read (all) posts about this and related threads you should
have noticed that I am and others running SCSI systems...

>
> even i dont get any skips when i run the player at nice -n -20.

During dbench 16/32 and higher? Are you sure?

-Dieter