[LAU] Re: difference between realtime-kernel and low-latency-kernel?

[Florian Schmidt]

On Thursday 04 October 2007, Jacob wrote:
> Hi,
>
> On Thu, Oct 04, 2007 at 10:29:56AM +0200, Florian Schmidt wrote:
> > [...]
> > And yes, i consider it a bug that top and other software report the
> > SCHED_FIFO prio as negative values. Where does that come from? Does the
> > prio already get listed as negative in /proc? Or do they simply do it to
> > separate the SCHED_FIFO threads from SCHED_OTHER threads? Anyways POSIX
> > speaks of positive SCHED_FIFO prios in the range 1..99 afaik..
>
> Hmmm, POSIX talks about priorities in the range of
>    min .. max,
>    where
>      min = sched_get_priority_min(alg)
>      max = sched_get_priority_max(alg)
>      max - min >= 32, if alg == SCHED_FIFO or alg == SCHED_RR
>      and alg being the the scheduling algorithm (like SCHED_FIFO, ...)
>
> Under Linux (according to 'man sched_get_priority_min') the follwoing
> ranges apply:
>      SCHED_FIFO  : min = 1, max = 99
>      SCHED_RR    : min = 1, max = 99
>      SCHED_OTHER : min = 0, max = 0


Ok thanks for clearing this up :) So in principle there actually even might be 
partially (or only) negative prios for SCHED_FIFO processes. 


Thanks,
Flo

-- 
Palimm Palimm!
http://tapas.affenbande.org