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Mon, 13 Apr 2026 11:20:32 -0700 (PDT) From: Brandon Ho X-Google-Original-From: Brandon Ho To: rpm@xenomai.org Cc: brandonho667@gmail.com, brho@relativityspace.com, jsridharan@relativityspace.com, xenomai@lists.linux.dev Subject: Re: Minor page faults from memory compaction causing in-band transitions Date: Mon, 13 Apr 2026 11:19:29 -0700 Message-ID: <20260413181929.1801013-1-brho@relativityspace.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <87v7e8yzhj.fsf@xenomai.org> References: <87v7e8yzhj.fsf@xenomai.org> Precedence: bulk X-Mailing-List: xenomai@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Thank you for the responses! I recently came across the `compact_unevictable_allowed` sysctl option and it seems like it could be a good fit for our use case. Setting it to 0 would prevent the kernel from compacting/migrating locked pages, which should eliminate the minor faults we're seeing during compaction. Could we possibly set `compact_unevictable_allowed=0` by default when CONFIG_EVL is enabled? https://www.infradead.org/~mchehab/kernel_docs/admin-guide/sysctl/vm.html#compact-unevictable-allowed