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Thu, 26 Feb 2026 15:48:06 -0800 (PST) Date: Thu, 26 Feb 2026 15:48:01 -0800 From: Isaac Manjarres To: Kalesh Singh Cc: anthony.yznaga@oracle.com, lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, Suren Baghdasaryan , android-mm Subject: Re: [LSF/MM/BPF TOPIC] mshare - sharing page tables across processes Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Stat-Signature: pwtwso66bbpngnyx93nhz1g9brtacmwr X-Rspamd-Queue-Id: 81CA6A000B X-Rspamd-Server: rspam07 X-Rspam-User: X-HE-Tag: 1772149688-815550 X-HE-Meta: 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 cm+bKGrV ohLzdtWIup8HimR33C1TuKBKM5ppnzPZzP+Sx30n74yxzBxvx4xx7gNLsK8eMoory6Tp55+RA9dtVE7m41IurP9Q+KH3wFb+H8ZiysjjKOSsOadaWbRvtZGTPgIaipVil1AD+Hc5n5ylQC8MyY2cKwuBoYMojxQlhWPaYjixNbA+1gtcGvh1+DOtza8OnBbFUTdNVMLb2GZJI3wixvxgwOuAZFWV71XuMdY282DUv6DjeTZoXViHPRaKmye3370hlI87aMlxuSfBg/ZCSsNGijHLw0qGZeJOOlxkpOJ5H3fxnvV7wZcApZc8JKygS22y804YtQqa1jL7F6qQkpbIItDjwh5M7d3ktrzHD2hVLfMsS0CGrTkkUtqGetjoTnUnXm7bYdicHTFBw5IRs+TOM1ozgMgBo2EjlQfrPypGob7ZgVWnEwIYhXinVrA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Feb 25, 2026 at 04:59:32PM -0800, Kalesh Singh wrote: > On Mon, Feb 23, 2026 at 6:12 PM wrote: > > > > mshare is a new form of shared memory that shares resources between > > processes, namely the page tables entries and VMAs of the shared > > objects. Advantages include reduced memory consumption through > > eliminating the need for duplicated PTEs in each process, reduced > > overhead needed to fault shared pages into multiple processes, and the > > ability for updates to the memory such as protection changes to be > > immdediately visible to all sharing processes. > > > > For some time now the proposed API has continued to evolve. With > > feedback from mm maintainers, a new approach using syscalls is being > > taken to create, attach, and deattach mshare regions and to map and > > manipulate the memory objects within a region. > > > > Let's discuss the current state of the API and technical challenges of > > managing and accomodating shared page tables in the kernel. > > > > Anthony > > > > > > References: > > > > https://lore.kernel.org/linux-mm/20250820010415.699353-1-anthony.yznaga@oracle.com/ > > https://lore.kernel.org/linux-mm/20250404021902.48863-1-anthony.yznaga@oracle.com/ > > Hi Anthony, > > I would be very interested in participating in this discussion at LSF/MM. > > As mentioned on the mailing list, we are currently exploring similar > optimizations to deduplicate page tables for Android's Zygote process. > I'd love to join the session to discuss how the proposed sharing > mechanisms might align. > > Thanks, > Kalesh Hello Anthony, I'm also working on optimizing pagetable usage in Android with Kalesh, so I'm definitely interested in participating in this discussion as well. Thanks, Isaac