Sound skips

[Iain Sandoe]

>> >>  You might want to try Andrew Morton's Low-Latency patch (URL:
>> >>  http://www.uow.edu.au/~andrewm/linux/schedlat.html#downloads)
>
> Done. It doen't make a lot difference, but I can compile stuff without
> sound interruptions most of the time

OK.  So nothing much has changed since I last tried it - note that those
patches take scheduling latency below 1ms on x86.

maybe we do have some IRQ blocking as well (I haven't had time to benchmark
that at 2.4.x - it's on the TODO list).

>(if it doesn't involve libtool).

hmmm.  Have you got any idea what libtool does that is different?
(does strace work at the moment?)

mmap-ing files is "bad news" even with the LL patches (IIRC).

> I tried to lower the fragment size to 9 (512B==0.012s) and it skips
> even when the system is completely idle.

I don't know what UI you are using but...

does this occur each second (i.e. related to, for example, updating a clock
on screen) ... or

every 20/30 seconds or so - perhaps related to sync() ?

---

ah well, we'll solve it eventually [otherwise PPC is dead for sound - which
would be a Great Shame (tm).]

ciao,
Iain.


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