On 10/07/2011 04:24 PM, Mel Gorman wrote:

On Fri, Oct 07, 2011 at 04:07:06PM -0400, Rik van Riel wrote:

quoted

On 10/07/2011 11:17 AM, Mel Gorman wrote:

quoted

If compaction can proceed, shrink_zones() stops doing any work but
the callers still shrink_slab(), raises the priority and potentially
sleeps.  This patch aborts direct reclaim/compaction entirely if
compaction can proceed.

Signed-off-by: Mel Gorman<mgorman@suse.de>

This patch makes sense to me, but I have not tested it like
the first one.

Do if you can.

I'll probably build a kernel with your patch in it on
Sunday - I'll be walking across a mountain tomorrow :)

It's marginal and could be confirmation bias on my part. Basically,
there is noise when this path is being exercised but there were fewer
slabs scanned.  However, I don't know what the variances are and
whether the reduction was within the noise or not but it makes sense
that it would scan less.  If I profiled carefully, I might be able
to show that a few additional cycles are spent raising the priority
but it would be marginal.

This seems clear enough.

While patch 1 is very clear, patch 2 depends on reviewers deciding it
"makes sense".

quoted

Having said that, I'm pretty sure the patch is ok :)

Care to ack?

Sure.

Acked-by: Rik van Riel <redacted>


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