From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9936E383C7C; Fri, 20 Mar 2026 14:45:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774017933; cv=none; b=M71b9hBfzqLjWy239k8O5Dfo5B4SL8u3+bhB1UfcUR9I83hyFcM8W5MMbVAkZuypsj7k4XLIIjNsBIWEnvgahQL1Bn4OSpwLWhXHCLE41xDKy970ZE0ZQXQZpA8YP9hqF1Nt8K/MVAUhCoESot6LJpd9CzcyggjN32nEig/jYVM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774017933; c=relaxed/simple; bh=myZR/UnlE+SI0oy9BRK0X+Y9scyat+qDRsNLHUTyFWg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=J81MqJ4pjzT00J8syCggWX19rY8SG0T8VdIm+AJVR6FrpPHBfR9cQpnlYVboR7mHUlgiePI0zldY0z7Ilr+mUkoLOdck4WWO79L8tFBc8+K0k8zpg8e1bmy2Oroswj4OYOmMSztY8hONvTb0Q1MFlE04gUdYPNOITKmM8N9LsdA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Unnq69Ql; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Unnq69Ql" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2451FC4CEF7; Fri, 20 Mar 2026 14:45:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774017933; bh=myZR/UnlE+SI0oy9BRK0X+Y9scyat+qDRsNLHUTyFWg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Unnq69QlXqH2oNBMdgOndbbuJ58+x6JSFqTk9uQ5zb89qOF3njkhcNNjP9kWH+4ld ER+pquzrTBUyXfL0XtbdK23k4XZTfLw24qqTlJVWB3tqgpoju6RRUjjCqibSy59Rv+ RoyH+sof7UukWsTxLUa0g7CCu7l2aq28AjIYyWoiIyI78nl0f0/Hyj0i4rYd5ytL/K DBzQhCHFIaHNo7MZgs+d5R6PTQDNd5Bh2Zn/G1sG439Lt2cAnZjXSOXc/eGI0DbhWw Pjy+kLZcHDB/+ij0Cba1zBo7wMa+UDIViAFIYfDbWPmw87NL7A/gBWJcz/wzjFkelD UIJFloVOLqhqw== From: SeongJae Park To: Liew Rui Yan Cc: SeongJae Park , linux-mm@kvack.org, damon@lists.linux.dev, linux-doc@vger.kernel.org, Andrew Morton Subject: Re: [PATCH] Docs/mm/damon: document min_nr_regions constraint and rationale Date: Fri, 20 Mar 2026 07:45:29 -0700 Message-ID: <20260320144530.91737-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260320052428.213230-1-aethernet65535@gmail.com> References: Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello Liew, Thank you for this patch! On Fri, 20 Mar 2026 13:24:28 +0800 Liew Rui Yan wrote: > The current DAMON implementation requires 'min_nr_regions' to be at > least 3. However, this constraint is not explicitly documented in the > admin-guide documents, nor is its design rationale explained in the > design document. > > Add a section in design.rst to explain the rationale: the virtual > address space monitoring design needs to handle at least three regions > to accommodate two large unmapped areas. While this is specific to > 'vaddr', DAMON currently enforces it across all operation sets for > consistency. > > Also update reclaim.rst and lru_sort.rst by adding cross-references to > this constraint within their respective 'min_nr_regions' parameter > description sections, ensuring users are aware of the lower bound. > > This change is motivated from a recent discussion [1]. > > [1] https://lore.kernel.org/damon/20260319151528.86490-1-sj@kernel.org/T/#t > > Signed-off-by: Liew Rui Yan Reviewed-by: SeongJae Park Thanks, SJ [...]