Kernel-lowlatency vs kernel-rt

Kaj Ailomaa zequence at mousike.me
Sat Nov 3 00:30:40 UTC 2012


On Fri, 02 Nov 2012 23:58:39 +0100, Ralf Mardorf  
<ralf.mardorf at alice-dsl.net> wrote:

> Hi :)
>
> on Ubuntu Studio Quantal I switched to
> $ uname -a
> Linux qrc 3.6.5-rt14 #1 SMP PREEMPT RT Fri Nov 2 21:36:37 CET 2012
> x86_64 x86_64 x86_64 GNU/Linux
>
> A kernel-rt seems to be much better on my machine.
>
> With the kernel-lowlatency for a very small audio session, CPU usage
> "< 10%", I get xruns with
>
> sample_rate=48000
> frames_period=512
>
> Now, with the kernel-rt everything seems to be [Ok] with
>
> frames_period=256
>
> but with frames_period=128 I get xruns again.
>
> Regards,
> Ralf
>

Did you compare with a lowlatency of the same kernel version?
If not, the test is not very conclusive.

If you like to see some good results from a lowlatency kernel, try 2.6.37,  
and perhaps also 2.6.38 and 2.6.39
As you might have experienced, something made kernels less reliable from  
somewhere around version 3.
I haven't tried 3.6 series yet.



More information about the Ubuntu-Studio-devel mailing list