What Parts of Linux Audio Simply Work Great? (was Re: [linux-audio-dev] Best-performing Linux-friendly MIDI interfaces?)

[fons adriaensen]

On Thu, Jun 16, 2005 at 10:57:51PM +0200, Florian Schmidt wrote:

> Ah, i remembered slightly incorrectly. Thanks Paul, for setting me
> straight in #ardour. The thing is that the DLL based client thread
> wakeup has the ever so slight possibility to do its thing too early.
> Thus coreaudio waits a bit more (the "safety offset"). 
> 
> It seems this safety offset is driver specific but usually ranges from
> 64 to 32 frames (i have no definite source for this, just a bit of
> googling). And with a sufficiently low period size used this accounts
> for pretty much an extra period of latency..

Strange... If you would program a timer using the info available from
jackd's DLL, it would never generate its interrupt before the HW is 
ready (i.e. has at least a period available). It would actually trigger
just after the interrupt it is derived from (the small average latency
that is not compensated). So I wonder what problem CoreAudio has with
this.

-- 
FA