On Tue, Feb 21, 2012 at 3:34 AM, Glauber Costa [off-list ref] wrote:

In the context of tracking kernel memory objects to a cgroup, the
following problem appears: we may need to destroy a cgroup, but
this does not guarantee that all objects inside the cache are dead.
This can't be guaranteed even if we shrink the cache beforehand.

The simple option is to simply leave the cache around. However,
intensive workloads may have generated a lot of objects and thus
the dead cache will live in memory for a long while.

Why is this a problem?

Leaving the cache around while there are still active objects in it
would certainly be a lot simpler to understand and implement.

-- Suleiman