Messages in this thread | | | Date | Mon, 29 Apr 2013 13:12:03 -0400 | From | Rik van Riel <> | Subject | Re: [PATCH 2/3] mm: Ensure that mark_page_accessed moves pages to the active list |
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On 04/29/2013 12:31 PM, Mel Gorman wrote:
> A PageActive page is now added to the inactivate list. > > While this looks strange, I think it is sufficiently harmless that additional > barriers to address the case is not justified. Unfortunately, while I never > witnessed it myself, these parallel updates potentially trigger defensive > DEBUG_VM checks on PageActive and hence they are removed by this patch.
Could this not cause issues with __page_cache_release, called from munmap, exit, truncate, etc.?
Could the eventual skewing of active vs inactive numbers break page reclaim heuristics?
I wonder if we would need to move to a scheme where the PG_active bit is always the authoritive one, and we never pass an overriding "lru" parameter to __pagevec_lru_add.
Would memory ordering between SetPageLRU and testing for PageLRU be enough to then prevent the statistics from going off?
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