[LAU] multi processor

[Fernando Lopez-Lezcano]

On Thu, 2009-01-29 at 22:24 +0300, alex stone wrote:
> I've done a bit of googling, but can't seem to find or understand
> information about linux (audio and vid specific, for example writing
> for film) and multicore, multi processors.
> 
> Example being a Mobo that supports quadcore/ 4 cpu. (Tyan)

You mean one quadcore processor or 4 quad core processors?

> Anyone using one of these monsters for audio/video, with linux?

We have one Supermicro H8QM3 with 4 quad core opteron 8356 processors
(16 cores in all!). Mostly for multi-threading and sound server
experimental stuff. Works fine so far but it is in the server room (very
noisy! :-)

> If so, what's the performance/compatibility like? Driver/module
> issues, things not working, etc..

On this particular mobo I've had problems with newer kernels (won't boot
correctly) that I have not debugged - I just keep using an older one. 

The performance depends on the software. Very little stuff out there is
properly multithreaded and can use more than one core. AFAIK pd,
supercollider, chuck, etc, etc, use only one core. CLM in its newer S7
Scheme incarnation does use multiple cores and Bill has reported very
good speedups in non-realtime synthesis. Faust can also generate
multithreaded code that scales very well. Stuff like mpeg encoders also
have parameters to enable more than one thread of execution. 

-- Fernando