site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Mar 17, 2006, at 7:53 AM, info@yourkit.com wrote: Hello, is there any way to get time which particular thread is being executed on CPU. In other words how many milliseconds (or nonoseconds) of CPU time was consumed by thread since it has been started. I'm writing CPU profiler for Mac OS X and thread CPU times is very important for me. Please advise. -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... IAIK, in Linux there is a clock_gettime(CLOCK_THREAD_CPUTIME_ID) system call (and Windows has similar API) but I cannot find any analog for Darwin. The best way is to do it by observation. This is what chud and shark do. Formal resource utilization accounting is only ever done on a per process or per task basis, not a per thread basis. If you want absolute values, there are two timers that are started for system and user time when threads are started that will provide this information from the scheduler. However, in order to access them, you will need to write a kext, and you will need to explicitly link against the mach_kernel instead of against one of the symbol sets, which will require that you recompile your application for each point release of the OS (e.g. 10.4.3->10.4.4, etc.). The closest hint I'm willing to give you is "look at the implementation of task_info()". How you link in such a way as to make your application not run except on a specific OS version has been discussed before (you will need to look at the list archives, or combine the results of two knowledge base articles from developer.apple.com) and for the identity of the timers themselves and how they are accessed, you will need to look at the source code on opendarwin.org. Basically, if you do this, you are on your own, since it touches on details of the microarchitecture, such as the relationship between tasks and processes, threads and uthreads, and how the scheduler works at the lowest level. We neither document nor guarantee not to change these things from point release to point release of the OS, and we steer internal tools developers away from doing this sort of thing as well. This email sent to site_archiver@lists.apple.com