Re: [PATCH] mm: meminit: Finish initialisation of struct pages before basic setup

[Mel Gorman <mgorman@suse.de>]

On Thu, May 07, 2015 at 03:09:32PM -0700, Andrew Morton wrote:
> On Thu, 7 May 2015 08:25:18 +0100 Mel Gorman <mgorman@suse.de> wrote:
> 
> > Waiman Long reported that 24TB machines hit OOM during basic setup when
> > struct page initialisation was deferred. One approach is to initialise memory
> > on demand but it interferes with page allocator paths. This patch creates
> > dedicated threads to initialise memory before basic setup. It then blocks
> > on a rw_semaphore until completion as a wait_queue and counter is overkill.
> > This may be slower to boot but it's simplier overall and also gets rid of a
> > section mangling which existed so kswapd could do the initialisation.
> 
> Seems a reasonable compromise.  It makes a bit of a mess of the patch
> sequencing.
> 
> Have some tweaklets:
> 

The tweaks are prefectly reasonable. As for the patch sequencing, I'm ok
with adding the patch on top if you are because that preserves the testing
history. If you're unhappy, I can shuffle it into a better place and resend
the full series that includes all the fixes so far.

Thanks.

-- 
Mel Gorman
SUSE Labs