cgutils.py 文件源码

def set_memory_hardlimit(cgrp, limit):
    """Set the cgroup hard-limits to the desired value.

    The logic here is complicated since the ordering of operations depends on
    weither we are lowering or raising the value.
    """
    def _lower_memory_hardlimit(cgrp, limit):
        """Lower the cgroup memory hardlimit."""
        cgroups.set_value('memory', cgrp,
                          'memory.limit_in_bytes', limit)
        cgroups.set_value('memory', cgrp,
                          'memory.memsw.limit_in_bytes', limit)

    def _raise_memory_hardlimit(cgrp, limit):
        """Raise the cgroup memory hardlimit."""
        cgroups.set_value('memory', cgrp,
                          'memory.memsw.limit_in_bytes', limit)
        cgroups.set_value('memory', cgrp,
                          'memory.limit_in_bytes', limit)

    memory_hardlimit_funs = [_lower_memory_hardlimit, _raise_memory_hardlimit]
    while memory_hardlimit_funs:
        try:
            memory_hardlimit_fun = memory_hardlimit_funs.pop(0)
            memory_hardlimit_fun(cgrp, limit)
            break

        except IOError as err:
            if err.errno == errno.EBUSY:
                # Resource busy, this means the cgroup is already using more
                # then the limit we are trying to set.
                raise TreadmillCgroupError('Unable to set hard limit to %d. '
                                           'Cgroup %r memory over limit.' %
                                           (limit, cgrp))

            elif err.errno == errno.EINVAL:
                # This means we did the hard limit operation in the wrong
                # order. If we have a different ordering to try, go ahead.
                if memory_hardlimit_funs:
                    continue

            # For any other case, raise the exception
            raise