Messages in this thread | | | Date | Tue, 6 Apr 2010 09:25:36 +0800 | From | Shaohua Li <> | Subject | Re: [PATCH]vmscan: handle underflow for get_scan_ratio |
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On Sun, Apr 04, 2010 at 10:19:06PM +0800, KOSAKI Motohiro wrote: > > On Fri, Apr 02, 2010 at 05:14:38PM +0800, KOSAKI Motohiro wrote: > > > > > > This patch makes a lot of sense than previous. however I think <1% anon ratio > > > > > > shouldn't happen anyway because file lru doesn't have reclaimable pages. > > > > > > <1% seems no good reclaim rate. > > > > > > > > > > Oops, the above mention is wrong. sorry. only 1 page is still too big. > > > > > because under streaming io workload, the number of scanning anon pages should > > > > > be zero. this is very strong requirement. if not, backup operation will makes > > > > > a lot of swapping out. > > > > Sounds there is no big impact for the workload which you mentioned with the patch. > > > > please see below descriptions. > > > > I updated the description of the patch as fengguang suggested. > > > > > > Umm.. sorry, no. > > > > > > "one fix but introduce another one bug" is not good deal. instead, > > > I'll revert the guilty commit at first as akpm mentioned. > > Even we revert the commit, the patch still has its benefit, as it increases > > calculation precision, right? > > no, you shouldn't ignore the regression case. I don't think this is serious. In my calculation, there is only 1 page swapped out for 6G anonmous memory. 1 page should haven't any performance impact.
Thanks, Shaohua
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