From patchwork Mon Oct 24 19:06:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13017996 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 7B488ECAAA1 for ; Mon, 24 Oct 2022 19:06:51 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 183CC940015; Mon, 24 Oct 2022 15:06:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1337694000C; Mon, 24 Oct 2022 15:06:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 021EA940015; Mon, 24 Oct 2022 15:06:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id E36D094000C for ; Mon, 24 Oct 2022 15:06:50 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id AF31B40279 for ; Mon, 24 Oct 2022 19:06:50 +0000 (UTC) X-FDA: 80056774980.10.DD15576 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf03.hostedemail.com (Postfix) with ESMTP id 4CC3C20032 for ; Mon, 24 Oct 2022 19:06:50 +0000 (UTC) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 9919B3ED5924; Mon, 24 Oct 2022 12:06:12 -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, willy@infradead.org, hch@infradead.org Subject: [RFC PATCH v3 14/14] mm: document /sys/class/bdi//min_bytes knob Date: Mon, 24 Oct 2022 12:06:03 -0700 Message-Id: <20221024190603.3987969-15-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221024190603.3987969-1-shr@devkernel.io> References: <20221024190603.3987969-1-shr@devkernel.io> MIME-Version: 1.0 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666638410; a=rsa-sha256; cv=none; b=jKE2z2mXUJIzkbFen8+mjR+kEIlgQkGVqRWRQJ1MSNdtOGDBa3ncjmeDADd3Uygkt5TyM7 1P+B0nzrmqd/OeVM4DuH3Ty9h59ThqHhLSfkCjGD/fEjKkARZpWFvMHvI19oFXzNYaVgiH gQe1YSWBa3qHrws6w0gWrWTWmfKDurc= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf03.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=1666638410; 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=aOfuDL/2N4WylY6TNjDd1lBhRdzTTmmky+flmNYJ9h+nt0f+7fcWDclIQ3UjMFoDP/fAG7 zjUtR0ZxrWB68NaKQ4ldR6PNXFVetiTI2vOmg1WKrLCSbR+N/eel/EXIoIa0AOX1k3UA3V nxr9ap0K8vNYZOsAMzNWndylw5+5KSQ= X-Stat-Signature: ebg3c6k1rs1pamos7zm5ybbkoey9wefy X-Rspamd-Queue-Id: 4CC3C20032 Authentication-Results: imf03.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf03.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-Rspamd-Server: rspam05 X-HE-Tag: 1666638410-897895 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