Re: [RFC] Arch option to touch newly allocated pages

Daniel Phillips
2002-03-07T17:59:58Z

On March 7, 2002 05:19 pm, Alan Cox wrote:
> > Higher order allocation - imho we can fix that too, eventually, however it's a lot
> > more work. First we have to have reliable physical defragmentation.
> >
> > > And if we are OOM - we want to return NULL
> >
> > What good does that do?
>
> It allows us to continue. It avoids the deadlocks.

Could you describe the deadlock, please?

> It lets the caller make an intelligent decision.

I maintain it's the wrong interface, we're mixing two concepts together there:

- VM can't find blocks that are freeable, so fails and dumps the problem
on the caller, which has to busy wait. This sucks.

- The VM is under heavy load and the caller doesn't really need the memory
that badly because it has a fallback, the VM somehow knows this, so fails
the allocation and everybody is happy.

These should be separated, and we should fix the former.

--
Daniel