informational files on the root cgroup which end up showing global
information available elsewhere shouldn't exist.
+- The default time unit is microseconds. If a different unit is ever
+ used, an explicit unit suffix must be present.
+
+- A parts-per quantity should use a percentage decimal with at least
+ two digit fractional part - e.g. 13.40.
+
- If a controller implements weight based resource distribution, its
interface file should be named "weight" and have the range [1,
10000] with 100 as the default. The values are chosen to allow