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charset=us-ascii Content-Disposition: inline In-Reply-To: <193da117-30b8-425a-b095-6fd8aca1c987@huawei.com> On Tue 03-09-24 09:50:48, mawupeng wrote: > > Drain remote PCP may be not that expensive now after commit 4b23a68f9536 > > ("mm/page_alloc: protect PCP lists with a spinlock"). No IPI is needed > > to drain the remote PCP. > > This looks really great, we can think a way to drop pcp before goto slowpath > before swap. We currently drain after first unsuccessful direct reclaim run. Is that insufficient? Should we do a less aggressive draining sooner? Ideally restricted to cpus on the same NUMA node maybe? Do you have any specific workloads that would benefit from this? -- Michal Hocko SUSE Labs