Messages in this thread | | | Date | Thu, 4 Jul 2013 10:32:11 +0100 | From | Mel Gorman <> | Subject | Re: [PATCH 12/13] mm: numa: Scan pages with elevated page_mapcount |
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On Wed, Jul 03, 2013 at 08:41:24PM +0200, Peter Zijlstra wrote: > On Wed, Jul 03, 2013 at 03:21:39PM +0100, Mel Gorman wrote: > > > Note that the patch still leaves shared, file-backed in VM_EXEC vmas in > > place guessing that these are shared library pages. Migrating them are > > likely to be of major benefit as generally the expectation would be that > > these are read-shared between caches and that iTLB and iCache pressure is > > generally low. > > I'm failing to grasp.. we don't migrate them because migrating them would > likely be beneficial? > > Missing a negative somewhere?
Yes.
Note that the patch does not migrate shared, file-backed within vmas marked VM_EXEC as these are generally shared library pages. Migrating such pages is not beneficial as there is an expectation they are read-shared between caches and iTLB and iCache pressure is generally low.
-- Mel Gorman SUSE Labs
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