[sc-dev] New PowerBooks, SC and CPU... ick...

[Joshua Parmenter <joshp@xxxxxxxxxxxxxxxx>]

Hi everyone,

I just got one of the new PB 1.67GHz machines, and there is a pretty  
significant problem that Apple says that can't solve on their end.

Basically, the ability to control the processor speed is gone on the  
new models. On the older one's you could open Energy Saver and tell  
the computer to always run at the top CPU speed. This has  
disappeared, and the new machines "automatically" adjust the CPU  
speed for CPU load. Problem is, this isn't very speedy (in SC terms  
at least). So, code that used to run at about a stable 40% on my old  
PB, now runs at 60% with HUGE spikes on the new one.

The new processors will halve and quarter their CPU load...  
basically, when very little is running, I really have a 417 MHz  
machine... but the second it jumps up (for instance when I start an  
expensive process), the processor can't handle it... Apple says there  
isn't a way to set the machine up to work the way the old one's did...

Does anyone think there is anyway to get scsynth to request the max  
CPU speed when started? Apparently there is some developer  
documentation about the new variable rate CPUs that I still need to  
track down, but this is a huge problem... anyone have any ideas?

Thanks,

Josh

******************************************
Joshua Parmenter
joshp@xxxxxxxxxxxxxxxx
Post-Doctoral Research Associate - Center for Digital Arts and  
Experimental Media
Raitt Hall - University of Washington
Seattle, Washington 98195

http://www.dxarts.washington.edu
http://www.realizedsound.net/josh/