[PlanetCCRMA] Moving to PlanetCCarma for low latency?

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Wed Aug 25 09:21:01 2004


On Wed, 2004-08-25 at 05:57, Steve Harris wrote:
> On Wed, Aug 25, 2004 at 02:02:49 +0200, Michele Spinolo wrote:
> > I'm planning to move to PlanetCCarma to build a realtime convolver (based
> > actually on BruteFIR and in future on AlmusVCU) to get as low latency as
> > possible.
> > I read some messages on this nice newsletter, speaking about latency
> > improved performance with FC2 and kernel 2.6.7 or newer.
> > 
> > Actually I'm running on Suse9.1 with Alsa 1.0.5a with kernel 2.6.5
> > partitioning with BruteFir up to 1024samples per packet (minimum packet size
> > allowed by my soundcard, Terratec EWS88D working with Ice1712 driver).
> > 
> > So I was wondering if moving to FC2, kernel 2.6.8.1 and Alsa 1.0.6a based on
> > PlanetCCarma distribution I could get better latency performances.
> 
> Probably not - if 1024 is the lowest your card can do moving to planet
> ccrma wont help. If your hardware could go lower it might let you use
> smaller buffer relaibly, but it its just latency and not reliability thats
> your problem, I dont think it will help.

It could help, I guess, because it would give the application more
"useful time to do work". Otherwise you have to have some free time to
be able to cope with the higher latencies and not trigger an xrun. 

But FC2/2.6 is not ready yet, I think :-(
-- Fernando