From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E177D74956 for ; Wed, 30 Oct 2024 01:44:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=kGTbvOlkl8NN9lF6u3rA7N7VkATyiMKw0698JsFPWOo=; b=oPiAyhCOZihUq9sz20me1a174V AezllvA8VKL/SqiRUjl41BGpTx91JzT7/9QJo46tEd/Wj8u/5/98vjGZYwLmDSlGOiSho7BqGD0rv Z8z3ZpXWxu/SOxkKD+b4smubiVljsgK8WPcToLbW7AIqB/g6VMYkgI2bcz4fC0W3WmioTN8V3frKj nVIdTg3bX8Ilwv0RZCFpjuZQMD303LhX9vOh8phCLHUWS4a/KbpHz8hU33s7yMfw1a0EvvgVleONx tkiJVw/kbf9jUpgJgf1w7Jw+mkcdMLiWe6RAoGPIzUhHNhxCw9CI9rocbFPJ1So6osmJ68b6IN2v1 s8HeTTyA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t5xlG-0000000GS1P-2204; Wed, 30 Oct 2024 01:44:38 +0000 Received: from out30-99.freemail.mail.aliyun.com ([115.124.30.99]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t5xlD-0000000GS0C-0Sv4 for linux-nvme@lists.infradead.org; Wed, 30 Oct 2024 01:44:37 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1730252671; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=kGTbvOlkl8NN9lF6u3rA7N7VkATyiMKw0698JsFPWOo=; b=fwBPO1BPW+mcf4xk6wQGDE2KhHoZ5LLbm9ucDCV1k/kMb/VJ9bgLvRmDErFMauFZL7Od7e/+vYwIBI4vHySLY9wmokGZiSn1syL8toJ0cE0He9Wah/1CRdQnQNFbluD82XGvObP9gBQ5U1pICWG4kY5zjNZEL9ACQDFvS6Em3Q8= Received: from 30.178.82.27(mailfrom:kanie@linux.alibaba.com fp:SMTPD_---0WIC.YRE_1730252667 cluster:ay36) by smtp.aliyun-inc.com; Wed, 30 Oct 2024 09:44:28 +0800 Message-ID: Date: Wed, 30 Oct 2024 09:44:25 +0800 MIME-Version: 1.0 User-Agent: =?UTF-8?B?TW96aWxsYSBUaHVuZGVyYmlyZCDmtYvor5XniYg=?= Subject: Re: [PATCH] nvmet: make nvmet_wq visible in sysfs To: Chaitanya Kulkarni Cc: "linux-nvme@lists.infradead.org" , "hch@lst.de" , "sagi@grimberg.me" References: <20241029014915.16646-1-kanie@linux.alibaba.com> <8b4591d7-f0bd-4e4c-b1b3-1b375f25bda0@nvidia.com> <0e90730a-74c0-401a-82bd-92fdbcd2cbe0@linux.alibaba.com> <1c6e0bfe-f476-4c07-a67c-b526b325b405@nvidia.com> From: Guixin Liu In-Reply-To: <1c6e0bfe-f476-4c07-a67c-b526b325b405@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241029_184435_801447_602E9FB9 X-CRM114-Status: GOOD ( 12.33 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org 在 2024/10/30 03:52, Chaitanya Kulkarni 写道: > On 10/28/24 23:46, Guixin Liu wrote: >> 在 2024/10/29 13:04, Chaitanya Kulkarni 写道: >>> On 10/28/24 18:49, Guixin Liu wrote: >>>> Make nvmet_wq visible in sysfs, allowing for tuning the it's attr >>>> through sysfs. >>>> >>>> Signed-off-by: Guixin Liu >>>> --- >>> do you happened have a usecase for this? >>> >>> -ck >> Sometimes, in order to respond promptly to certain events or >> >> manage commands, we need to reserve resources and partition >> >> the CPU cores. For example, if there are 4 cores available, >> >> we can initially allocate them by dedicating one core for >> >> management while the remaining 3 cores are specifically for handling IO. >> >> Best Regards, >> >> Guixin Liu >> > I'm aware of exposing tunables through sysfs and it's benefits, my question > was do you have a setup where this setting is needed currently ? > > I've always been asked to for the usecase on a patch when we expose > something > out of kernel that is solving the problem in the deployment ... > > -ck I need serverve some cpu core to do other things, such as handle events and managements, so that the nvmet_wq can't running on all cpu cores, currently, I restrict it by setting the cpumask of nvmet_wq（that's why I expose nvmet_wq to sysfs）. Best Regards, Guixin Liu >