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[109.81.95.153]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4950872424asm132311495e9.1.2026.07.15.00.12.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2026 00:12:16 -0700 (PDT) Date: Wed, 15 Jul 2026 09:12:15 +0200 From: Michal Hocko To: Altan Hacigumus Cc: Andrew Morton , David Hildenbrand , Johannes Weiner , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Jiayuan Chen , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/vmscan: clear hopeless kswapd when global direct reclaim makes progress Message-ID: References: <20260710024429.70923-1-ahacigu.linux@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Tue 14-07-26 19:32:04, Altan Hacigumus wrote: > On Tue, Jul 14, 2026 at 4:34 AM Michal Hocko wrote: [...] > [2] Also, there is one more condition I've been looking at, from the > Sashiko review (a theoretical corner): skip the reset while tasks are > throttled on pfmemalloc_wait, so that it cannot defer the hopeless > escape hatch in allow_direct_reclaim(). I would keep this a separate patch with separate reasoning. Ideally with some way to trigger the behavior and prove it makes any practical meaning. Theoretical corner cases might backfire in this rather convoluted area. -- Michal Hocko SUSE Labs