site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com John wrote: In the scheduler ? I doubt it What are you trying to achieve ? S a m ------------------------------------------------------- Drawing on my fine command of language, I said nothing. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... Does the Darwin 7.4 (or later) kernel scheduler take CPU temperature into account at all? I've been poring over the xnu source trying to find a place where CPU temp is involved in some sort of thread priority or scheduling calculation, but have not found one yet. I'm hoping it'll be faster to just ask here :) The temperature of the CPU(s) is not gleaned by reading a register, at least not on PowerPC. You would set ( in supervisor mode ) a threshold watchpoint, and when the threshold is breached an interrupt is generated. It is CPU model dependent, in fact it might even be optional for PowerPC. Different strategies can be employed to cool down the CPU(s), spinning up a fan isn't a bad one :) How temperature shifts are handled by Apple could well be considered a competitive advantage. This is no word of authority but my guess would be that it is handled by AppleThermal.kext which appears to be closed source. This email sent to site_archiver@lists.apple.com