[64studio-devel] [64 Studio] #287: Possible kernel regression with high jackd sample rates in 32-bit version

[Dick Wright]

Daniel

There are no differences that I can discern. No power saving, nothing 
else taking processor power, hdparm settings the same and both using 
Gnome. There will be numerous differences in programme versions though. 
However, it does not get to run jack at the higher rates, it bombs out 
before it connects. I recall that the earlier versions of DeMudi would 
not connect at 96k either

I have just run a comparison of loading using Ardour using various 
versions on my hardware. I played back a four-channel recording with 
three effect at 44.1 k and 128 sample buffer, 5.8 milliseconds delay. On 
DeMudi it used 33% processor and on 64Studio 1.4, kernel 2.6.19 it uses 
58% and similar with 2..6.19.

My system is a 1.8GHz Athlon with an nforce 2 chip set and 1G ram. Not 
the most up-to-date but it just about does what I want - particularly 
using DeMudi. My sound card is a Maudio 24/96.

Regards

Dick

In message <464C4403.9040902 at 64studio.com>, Daniel James 
<daniel at 64studio.com> writes
>Hi Dick,
>
>> Jack is perfectly stable at 44.1k, full duplex running
>> six or eight channels on ardour. I rarely get an xrun. It will run 
>>simplex at 96k but not reliably. In duplex mode at 96k, it drops out 
>>on  the watchdog without ever connecting. I have not come across any 
>>other problems in 1.3.0
>
>It would be helpful to identify any significant differences between 
>your 64 Studio and DeMuDi installations. Obviously the kernel is 
>different, but for example:
>
>Desktop (fluxbox/gnome)
>System services running
>hdparm settings
>power management (eg. CPU frequency scaling)
>
>Cheers!
>
>Daniel

-- 
Regards

Dick Wright