[ckrm-tech] [PATCH 0/7] containers (V7): Generic Process Containers

[Paul Menage]

On 2/12/07, Sam Vilain <sam at vilain.net> wrote:
> Ask yourself this - what do you need the container structure for so
> badly, that virtualising the individual resources does not provide for?

Primarily, that otherwise every module that wants to affect/monitor
behaviour of a group of associated processes has to implement its own
process grouping abstraction.

As an example, the CPU accounting patch that in included in my patch
set as an illustration of a simple resource monitoring module is just
250 lines, almost entirely in one file; if it also had to handle
associating tasks together into groups and presenting a filesystem
interface to the user it would be far larger and would have a much
bigger footprint on the kernel.

>From the point of view of the virtual server containers, the advantage
is that you're integrated with a standard filesystem interface for
determining group membership. It does become simpler to combine
virtual servers and resource controllers, although I grant you that
you could juggle that from userspace without the additional kernel
support.

Paul