| Date | Wed, 8 Jun 2016 17:03:58 +0900 | From | Minchan Kim <> | Subject | Re: [PATCH 06/10] mm: remove unnecessary use-once cache bias from LRU balancing |
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On Mon, Jun 06, 2016 at 03:48:32PM -0400, Johannes Weiner wrote: > When the splitlru patches divided page cache and swap-backed pages > into separate LRU lists, the pressure balance between the lists was > biased to account for the fact that streaming IO can cause memory > pressure with a flood of pages that are used only once. New page cache > additions would tip the balance toward the file LRU, and repeat access > would neutralize that bias again. This ensured that page reclaim would > always go for used-once cache first. > > Since e9868505987a ("mm,vmscan: only evict file pages when we have > plenty"), page reclaim generally skips over swap-backed memory > entirely as long as there is used-once cache present, and will apply > the LRU balancing when only repeatedly accessed cache pages are left - > at which point the previous use-once bias will have been neutralized. > > This makes the use-once cache balancing bias unnecessary. Remove it. > > Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Minchan Kim <minchan@kernel.org>
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