[linux-audio-user] performance with AMD64

[Cezar]

Hello,

I am using Ubuntu Dapper on an amd64 athlon +3400 (laptop) with 
2.6.15-26-amd64-generic SMP PREEMPT kernel. My audio interface is a 
RMC Multiface II / Cardbus. I've manually compile alsa 1.0.12rc2.

I think the audio performance is way wrong :

with jackd -R -dalsa -r48000 -p128 -n2 -D -Chw:1,0 nothing else, I get
1.2% - 1.9% CPU usage if I don't do anything. When I load zynaddsubfx
it goes to 13%, again without touching the midi keybooard. By holding
C major chord with the default sound zynaddsubfx starts, I get a CPU
usage of 20%.

with jackd -R -dalsa -r48000 -p256 -n2 -D -Chw:1,0 nothing else, I get
0.65% - 0.96% CPU usage if I don't do anything. When I load 
zynaddsubfx it goes to 7.2% - 8%, again without touching the midi
keybooard. By holding C major chord with the default sound zynaddsubfx
starts, I get a CPU usage of 11%.

Could anyone please test something similar to my setup and post here ?
I don't think this is normal.

Thanks !