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

From: Daniel Phillips (phillips@bonn-fries.net)
Date: Thu Mar 07 2002 - 12:54:05 EST


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
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Thu Mar 07 2002 - 21:01:05 EST