Re: [PATCH 0/3] Reduce impact to overall system of SLUB using high-order allocations

Mel Gorman
2011-05-13T11:24:36Z

On Thu, May 12, 2011 at 08:04:57PM +0200, Andrea Arcangeli wrote:
> Hi James!
>
> On Wed, May 11, 2011 at 05:34:27PM -0500, James Bottomley wrote:
> > Yes, but only once in all the testing. With patches 1 and 2 the hang is
>
> Weird patch 2 makes the large order allocation without ~__GFP_WAIT, so
> even COMPACTION=y/n shouldn't matter anymore. Am I misreading
> something Mel?
>
> Removing ~__GFP_WAIT from patch 2 (and adding ~__GFP_REPEAT as a
> correctness improvement) and setting COMPACTION=y also should work ok.
>

should_continue_reclaim could till be looping unless __GFP_REPEAT is
cleared if CONFIG_COMPACTION is set.

> Removing ~__GFP_WAIT from patch 2 and setting COMPACTION=n is expected
> not to work well.
>
> But compaction should only make the difference if you remove
> ~__GFP_WAIT from patch 2.

--
Mel Gorman
SUSE Labs