Re: [RFC][PATCH 0/1] MAZE: Mazed processes monitor

Hirofumi Nakagawa
2008-05-22T09:36:47Z

Hi Andrew,

Thank you for your comment and review.

> The immediate quesstion is, of course, "why does this need to be done
> in-kernel?". I am unable to answer that from the provided changelog
> information, and I should be able to do that.

It needs to be done in kernel because excessive CPU cycle usage
is directly detected watching kernel internal task_struct.state.
It's hard to get that information outside the kernel.

Additionally, this patch's aim is to implement a
CGL (Carrier Grade Linux) requirement (AVL.14.0).

There are specs that can not be implemented outside the kernel.
These are;
- Communication between the monitoring process and the kernel
- Ability to define policy based on process events including
process/thread creation and exit, and,
- Ability to set the CPU cycle threshold to a resolution of
one millisecond.