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Mon, 16 Feb 2026 06:34:35 -0500 (EST) Date: Mon, 16 Feb 2026 11:34:30 +0000 From: Kiryl Shutsemau To: Wenchao Hao Cc: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: Add AnonZero accounting for zero-filled anonymous pages Message-ID: References: <20260214084514.2842745-1-haowenchao22@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=us-ascii Content-Disposition: inline In-Reply-To: <20260214084514.2842745-1-haowenchao22@gmail.com> On Sat, Feb 14, 2026 at 04:45:14PM +0800, Wenchao Hao wrote: > Add kernel command line option "count_zero_page" to track anonymous pages > have been allocated and mapped to userspace but zero-filled. > > This feature is mainly used to debug large folio mechanism, which > pre-allocates and map more pages than actually needed, leading to memory > waste from unaccessed pages. > > Export the result in /proc/pid/smaps as "AnonZero" field. I expect it to slowdown /proc/pid/smaps read substantially. I don't think this line in smaps worth it. -- Kiryl Shutsemau / Kirill A. Shutemov