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[2620:137:e000::1:20]) by mx.google.com with ESMTP id f9-20020a170906048900b00992fef5cff9si10520486eja.497.2023.09.06.20.15.10; Wed, 06 Sep 2023 20:15:40 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=ohoS0Q5N; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241038AbjIGC3q (ORCPT + 99 others); Wed, 6 Sep 2023 22:29:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33376 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241928AbjIGC3o (ORCPT ); Wed, 6 Sep 2023 22:29:44 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4DE119A6; Wed, 6 Sep 2023 19:29:40 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0184BC433C7; Thu, 7 Sep 2023 02:29:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694053780; bh=EttCSXcWQaBCLpMduSaDVf+bO6xFKw8ChvQvuGULuQo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ohoS0Q5NTqWvbTzBXP57Dq2ofbn2QBljXe1cpT6j4lRuQzRB3V3WC0/jjWNW9zKsh Pj0L+aNe9DpvOK+7f35EDNXepLHd2afINFwGotsGZrvFObI/8v0cnnEYpBOI2JUYmH /zr4DyQSRbrTK5dB2xtxZlxJVBO3UwjdbgcXEKRHJ7oe+HD6kjIPk8WJR4qzpiLMez orXkcK9BjJfpw0WtGMGlpGtkR3tkbB/jErb9/Dcmbg7Npz4s11Z0ecchpXsRgN5L5M t0gpXfrIaxSegMGSQeogKMEwEIC3I5l9+WKq0T+o70jZ9Bez1OALFBaPB6txHNOCkN ks7bnKiPNy1Vg== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , Jonathan Corbet , damon@lists.linux.dev, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 04/11] Docs/mm/damon/design: explicitly introduce ``nr_accesses`` Date: Thu, 7 Sep 2023 02:29:22 +0000 Message-Id: <20230907022929.91361-5-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230907022929.91361-1-sj@kernel.org> References: <20230907022929.91361-1-sj@kernel.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1776347031614754606 X-GMAIL-MSGID: 1776347031614754606 The design document is explaining about the access tracking mechanism and the access rate counter (nr_accesses), but not directly mentions the name. Add a sentence for making it clear. Signed-off-by: SeongJae Park --- Documentation/mm/damon/design.rst | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index a20383d01a95..5c465835a44f 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -163,9 +163,10 @@ assumption (pages in a region have the same access frequencies) is kept, only one page in the region is required to be checked. Thus, for each ``sampling interval``, DAMON randomly picks one page in each region, waits for one ``sampling interval``, checks whether the page is accessed meanwhile, and -increases the access frequency of the region if so. Therefore, the monitoring -overhead is controllable by setting the number of regions. DAMON allows users -to set the minimum and the maximum number of regions for the trade-off. +increases the access frequency counter of the region if so. The counter is +called ``nr_regions`` of the region. Therefore, the monitoring overhead is +controllable by setting the number of regions. DAMON allows users to set the +minimum and the maximum number of regions for the trade-off. This scheme, however, cannot preserve the quality of the output if the assumption is not guaranteed.