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WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.24] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemd200004.china.huawei.com (7.185.36.141) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: B21BE40009 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: mz753d9f1ofabtw9jdh4eh1ryri117zd X-HE-Tag: 1700636277-968917 X-HE-Meta: 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 HmVt8aoI w9yNLrogofuOgWAuTUVv0D6UpfkINNBbDPLx/DC4WPm6I6zYYRMdr4fWv23YE7GvObO9oVHOoBTPTfqH1FkLgt0Rc5BA2i8NSWaR+pcFFv9h7J6l5eiMezmXpmBj1NuL0++QN X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2023/11/21 21:00, Michal Hocko wrote: > On Tue 21-11-23 17:06:24, Liu Shixin wrote: > > However, in swapcache_only mode, the scan count still increased when scan > non-swapcache pages because there are large number of non-swapcache pages > and rare swapcache pages in swapcache_only mode, and if the non-swapcache > is skipped and do not count, the scan of pages in isolate_lru_folios() can > eventually lead to hung task, just as Sachin reported [2]. > I find this paragraph really confusing! I guess what you meant to say is > that a real swapcache_only is problematic because it can end up not > making any progress, correct? This paragraph is going to explain why checking swapcache_only after scan += nr_pages; > > AFAIU you have addressed that problem by making swapcache_only anon LRU > specific, right? That would be certainly more robust as you can still > reclaim from file LRUs. I cannot say I like that because swapcache_only > is a bit confusing and I do not think we want to grow more special > purpose reclaim types. Would it be possible/reasonable to instead put > swapcache pages on the file LRU instead? It looks like a good idea, but I'm not sure if it's possible. I can try it, is there anything to pay attention to? Thanks,