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Howlett" , Lorenzo Stoakes , Mike Rapoport , Suren Baghdasaryan , Vlastimil Babka , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH RFC] fs: drop_caches: introduce per-node drop_caches interface Message-ID: References: <20260409063503.3475420-1-wangkefeng.wang@huawei.com> <20260409081619.34f172dad0e5a56923b7eb2d@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: A470A180005 X-Stat-Signature: 4osgg4po5ntyh5jo7ir6ebj31db6korr X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1775767149-473592 X-HE-Meta: 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 soLer6vp wY+HZ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Apr 09, 2026 at 09:41:12PM +0200, Michal Hocko wrote: > > Our caching strategies might not be fitting all existing usecases but as > usual we are targetting as many of them as viable. The problem with > drop_caches is that it has grown unproportianal amount of cargo cult and > grown into "solution for any performance problems" magic pill. Even when > proven to cause more problems than it solves so many times. Again and > again. That is really sad. Same as THP causes more problems than it > solves and that you should be using 2GB of swap space or that swap out > is a signal of a disaster. There are more and they are hard to die. > I get a kick out of seeing articles like this still being published: https://kb.netapp.com/on-prem/ontap/da/NAS/NAS-KBs/What_are_the_differences_between_hard_mount_and_soft_mount 'intr' and 'nointr' have been no-ops since 2007 -- eighteen years before this article was last updated. We should make more things no-ops.