From patchwork Sat Nov 19 00:52:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13049533 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4790FC433FE for ; Sat, 19 Nov 2022 02:33:49 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 224246B0073; Fri, 18 Nov 2022 21:33:48 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1BA366B0075; Fri, 18 Nov 2022 21:33:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E5A6E8E0002; Fri, 18 Nov 2022 21:33:47 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id CC8936B0073 for ; Fri, 18 Nov 2022 21:33:47 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 92441C051A for ; Sat, 19 Nov 2022 02:33:47 +0000 (UTC) X-FDA: 80148621294.01.1F2ED7E Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf17.hostedemail.com (Postfix) with ESMTP id AD66140009 for ; Sat, 19 Nov 2022 02:33:45 +0000 (UTC) Received: by dev0134.prn3.facebook.com (Postfix, from userid 425415) id 9E02919380F1; Fri, 18 Nov 2022 16:52:18 -0800 (PST) From: Stefan Roesch To: kernel-team@fb.com, linux-block@vger.kernel.org, linux-mm@kvack.org Cc: shr@devkernel.io, axboe@kernel.dk, clm@meta.com, akpm@linux-foundation.org Subject: [RFC PATCH v4 20/20] mm: document /sys/class/bdi//min_ratio_fine knob Date: Fri, 18 Nov 2022 16:52:15 -0800 Message-Id: <20221119005215.3052436-21-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221119005215.3052436-1-shr@devkernel.io> References: <20221119005215.3052436-1-shr@devkernel.io> MIME-Version: 1.0 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1668825225; a=rsa-sha256; cv=none; b=6q/CAIjUfntps0VDZE41fplLWDDF7xjojpHxU1gAcXnO9cEPWBPOQeYt9Di/pujIF6pQ1y JNMpCzSFm82isHAtP++mGT1kTxoX041P3xH15M1RtNerODZgc19TV4vNSczFElnKLIyXIy ikrdXqNYmIcI3q3HwIswstFoC0n6eXo= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf17.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668825225; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=IAql0XPMvC1TJMJyXmTl7aDi/qXiRQy//kR7ZQ4/jNQ=; b=3fYHhbk1E7ds1afA4M5HAwj4hMleOTd5pD+GQVcz33Zz4fb8VlFG/U+AJAhoGsWY2GTV5X 96GblWd/qLf8mloxpiwMw+n535rYk206r39jPvglzO/dm9n48G4LR+V2UGbCEwqo9meoyh mirMmJ02qrjbIm7YxhtYGXlUujP9A/A= Authentication-Results: imf17.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf17.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io X-Rspam-User: X-Stat-Signature: ukmcyzhbh9nh4nega7dnbzxiwnp9rdpb X-Rspamd-Queue-Id: AD66140009 X-Rspamd-Server: rspam11 X-HE-Tag: 1668825225-509420 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This documents the new /sys/class/bdi//max_ratio_fine knob. Signed-off-by: Stefan Roesch --- Documentation/ABI/testing/sysfs-class-bdi | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi index 34d2e5489c74..b4ed0db680cf 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -44,6 +44,21 @@ Description: (read-write) +What: /sys/class/bdi//min_ratio_fine +Date: November 2022 +Contact: Stefan Roesch +Description: + Under normal circumstances each device is given a part of the + total write-back cache that relates to its current average + writeout speed in relation to the other devices. + + The 'min_ratio_fine' parameter allows assigning a minimum reserve + of the write-back cache to a particular device. The value is + expressed as part of 1 million. For example, this is useful for + providing a minimum QoS. + + (read-write) + What: /sys/class/bdi//max_ratio Date: January 2008 Contact: Peter Zijlstra