From patchwork Tue Oct 11 01:00:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13003490 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 64C19C433F5 for ; Tue, 11 Oct 2022 01:01:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BB52A80008; Mon, 10 Oct 2022 21:01:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B63A780007; Mon, 10 Oct 2022 21:01:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A037E80008; Mon, 10 Oct 2022 21:01:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 8BE5280007 for ; Mon, 10 Oct 2022 21:01:35 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 5C7CFC1005 for ; Tue, 11 Oct 2022 01:01:35 +0000 (UTC) X-FDA: 80006865750.26.5C87051 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf05.hostedemail.com (Postfix) with ESMTP id F19D6100025 for ; Tue, 11 Oct 2022 01:01:34 +0000 (UTC) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 3A7F134BDDEA; Mon, 10 Oct 2022 18:01:06 -0700 (PDT) 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 Subject: [RFC PATCH v1 14/14] mm: document new /sys/class/bdi//min_bytes knob Date: Mon, 10 Oct 2022 18:00:44 -0700 Message-Id: <20221011010044.851537-15-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221011010044.851537-1-shr@devkernel.io> References: <20221011010044.851537-1-shr@devkernel.io> MIME-Version: 1.0 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665450095; 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=3EUi6jPj2vZbV6ealsadFNrxvkct4936SBuSwS/JJic=; b=4KWi8ihFg5Ql32eEaZaNcyTJ9hWD55t2k3rxRHlbaBOUppPmSFs9hYb09hYJeokqz+yh8b +cYvEWqvVR2/S6WokYgnmC6l0yRLD9OYZIORft4VLgY7fzSKDeCnsBOiRBRd1jOwYMcfjp C0OGx/9FrKtw3PL8ZDjfqizqJN/4QtE= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none; spf=neutral (imf05.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665450095; a=rsa-sha256; cv=none; b=Lu7G4+FbK5oX/AvTN4+b133LN4pjPxC7BJd0kgeafBnuVUMnfMEUIWt72gmSWainb+YWtR ZU+gr73I+kgWznZfIxLHs7VUmam6Gs39QMzGkyCu2Dmk531xqqbzm6+EzyiqIgld0qswit kMnWOtzP30DZXjnSrBXrXhi1wb5xgxU= X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: F19D6100025 X-Stat-Signature: qmjhmb1weu7y5m98bdh7r89dkmpzuqam Authentication-Results: imf05.hostedemail.com; dkim=none; spf=neutral (imf05.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io; dmarc=none X-HE-Tag: 1665450094-920695 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//min_bytes 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 580f723de049..bec996e29565 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -57,6 +57,21 @@ Description: (read-write) +What: /sys/class/bdi//min_bytes +Date: October 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_bytes' parameter allows assigning a minimum + percentage of the write-back cache to a particular device + expressed in bytes. + For example, this is useful for providing a minimum QoS. + + (read-write) + What: /sys/class/bdi//max_bytes Date: October 2022 Contact: Stefan Roesch