2020년 3월 12일 (목) 오후 11:47, Johannes Weiner <hannes@xxxxxxxxxxx>님이 작성: > > On Thu, Feb 20, 2020 at 02:11:45PM +0900, js1304@xxxxxxxxx wrote: > > From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > > > > Current implementation of LRU management for anonymous page has some > > problems. Most important one is that it doesn't protect the workingset, > > that is, pages on the active LRU list. Although, this problem will be > > fixed in the following patchset, the preparation is required and > > this patch does it. > > > > What following patchset does is to restore workingset protection. In this > > case, newly created or swap-in pages are started their lifetime on the > > inactive list. If inactive list is too small, there is not enough chance > > to be referenced and the page cannot become the workingset. > > > > In order to provide enough chance to the newly anonymous pages, this patch > > makes active/inactive LRU ratio as 1:1. > > Patch 8/9 is a revert of this patch. I assume you did this for the > series to be bisectable and partially revertable, but I'm not sure > keeping only the first and second patch would be safe: they reduce > workingset protection quite dramatically on their own (on a 10G system > from 90% of RAM to 50% e.g.) and likely cause regressions. > > So while patch 2 is probably a lot better with patch 1 than without, Yes, it is what I intended. > it seems a bit unnecessary since we cannot keep patch 2 on its own. We > need the rest of the series to make these changes. Yes, you're right. > On the other hand, the patch is small and obviously correct. So no > strong feelings either way. Okay. I will keep the patches since I think that these patches will help someone who want to understand the LRU management. > > Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > > Reviewed-by: Johannes Weiner <hannes@xxxxxxxxxxx> Thanks!
