site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com Ryan rmcgann@mac.com _______________________________________________ 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... I would like to retrieve the current cpu frequency of each cpu/core installed (this frequency can change depending on the use -thanks to the intel speedstep technology-). Does anyone know which system call should be use to do so? I believe everybody so far has misread your question. As I read it, you want to know the CPU frequency of EACH core, and as you rightly state, individual cores can be throttled and/or shut down on newer Intels. sysctl only gives you information for *A* core, not all cores. Whether or not Mac OS X takes advantage of this feature of SpeedStep, I am not sure. I believe you might have to step into the Mach interfaces for host info; start researching <mach/host_info.h>. I've used host_info only sparingly, so I'll let somebody iwth more experience tell you if you those interfaces can give you the information you need and how to use them. Also, somebody from Apple will (rightly) discourage you, as these interfaces are "SPI" and not API--as I like to say "somewhat private interfaces" that might change in the future. This email sent to site_archiver@lists.apple.com