_psbsd.py 文件源码

def cpu_count_physical():
        """Return the number of physical CPUs in the system."""
        # From the C module we'll get an XML string similar to this:
        # http://manpages.ubuntu.com/manpages/precise/man4/smp.4freebsd.html
        # We may get None in case "sysctl kern.sched.topology_spec"
        # is not supported on this BSD version, in which case we'll mimic
        # os.cpu_count() and return None.
        ret = None
        s = cext.cpu_count_phys()
        if s is not None:
            # get rid of padding chars appended at the end of the string
            index = s.rfind("</groups>")
            if index != -1:
                s = s[:index + 9]
                root = ET.fromstring(s)
                try:
                    ret = len(root.findall('group/children/group/cpu')) or None
                finally:
                    # needed otherwise it will memleak
                    root.clear()
        if not ret:
            # If logical CPUs are 1 it's obvious we'll have only 1
            # physical CPU.
            if cpu_count_logical() == 1:
                return 1
        return ret