Messages in this thread | | | Date | Fri, 20 Nov 2020 15:19:48 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH next] mm/swap.c: reduce lock contention in lru_cache_add |
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On Fri, 20 Nov 2020 16:27:27 +0800 Alex Shi <alex.shi@linux.alibaba.com> wrote:
> The current relock logical will change lru_lock when found a new > lruvec, so if 2 memcgs are reading file or alloc page at same time, > they could hold the lru_lock alternately, and wait for each other for > fairness attribute of ticket spin lock. > > This patch will sort that all lru_locks and only hold them once in > above scenario. That could reduce fairness waiting for lock reget. > Than, vm-scalability/case-lru-file-readtwice could get ~5% performance > gain on my 2P*20core*HT machine.
But what happens when all or most of the pages belong to the same lruvec? This sounds like the common case - won't it suffer?
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