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

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?



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