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From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
To: Mel Gorman <mel@csn.ul.ie>
Subject: Re: [PATCH 10/11] Direct compact when a high-order allocation fails
Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton <akpm@linux-foundation.org>,
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> > Viewpoint 5. end user surprising
> > 
> > lumpy reclaim can makes swap-out even though the system have lots free
> > memory. end users very surprised it and they can think it is bug.
> > 
> > Also, this swap activity easyly confuse that an administrator decide when
> > install more memory into the system.
> > 
> 
> Compaction in this case is a lot less surprising. If there is enough free
> memory, compaction will trigger automatically without any reclaim.

I fully agree this.