Re: [PATCH 3/3] mm: slub: Default slub_max_order to 0

Christoph Lameter
2011-05-12T18:16:23Z

On Thu, 12 May 2011, Andrea Arcangeli wrote:

> On Thu, May 12, 2011 at 01:03:05PM -0500, Christoph Lameter wrote:
> > On Thu, 12 May 2011, Andrea Arcangeli wrote:
> >
> > > even order 3 is causing troubles (which doesn't immediately make lumpy
> > > activated, it only activates when priority is < DEF_PRIORITY-2, so
> > > after 2 loops failing to reclaim nr_to_reclaim pages), imagine what
> >
> > That is a significant change for SLUB with the merge of the compaction
> > code.
>
> Even before compaction was posted, I had to shut off lumpy reclaim or
> it'd hang all the time with frequent order 9 allocations. Maybe lumpy
> was better before, maybe lumpy "improved" its reliability recently,

Well we are concerned about order 2 and 3 alloc here. Checking for <
PAGE_ORDER_COSTLY to avoid the order 9 lumpy reclaim looks okay.