On 10/4/07, John <[EMAIL PROTECTED]> wrote: > > Is there a way to find the number of processors on a machine (on linux/ > windows/macos/cygwin) using python code (using the same code/cross > platform code)?
There's no single call that will give you the same info on every platform, but you can obviously write this yourself and switch based on os.uname()[0] in most cases. For Darwin, you can just use the subprocess module to call 'sysctl hw.logicalcpu'. I'm not sure if there's a more direct way in python to use sysctl. (hw.logicalcpu_max is what the hardware maximally supports, but someone may have started their machine with OF blocking some of the processors and you should probably respect that decision) For Linux you can read /proc/cpuinfo and parse that information. Be somewhat careful with this, however, if your processors support HT, they will show as 2, and that may or may not be what you want. You can deterministically parse this information out if you know which processor families are truly multi-core, and which are HT. For Win32, the cheap and dirty way is to read the NUMBER_OF_PROCESSORS environment variable. 99% of the time, this will be correct, so it might be sufficient for your purposes. There is a system call available on windows that will net you the true number of virtual cpus, but I don't know what it is. I don't have a cygwin install laying around, but my guess is there's a sysctl option there too. One note: *all* of these methods will tell you the virtual number of CPUs in a machine, not the physical number. There's almost no reason why you care about the distinction between these two numbers, but if you do, you'll have to go to great lengths to probe the actual hardware on each platform. (And pre-WinXP, Windows doesn't actually know the difference - all processors are presumed to be physical). Also, Darwin and Linux will easily allow you to get the speed of the processors, but on x86 these numbers are not the maximums due to C1E and EIST (x86 processors from all vendors are capable of changing speeds depending on load). -- Nick -- http://mail.python.org/mailman/listinfo/python-list
