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 08D76C4345F for ; Mon, 6 May 2024 05:33:28 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/PAELLSYDWiqyipZM5E9btis/ZO7gd0J7ISssEsRBds=; b=nECB8MSWeqqxuKKlODI1dXlN5P 8ki4SHoFsQUvJwQOCml98aE4YFFFHsJ8xT7pfG6vuTgfwDkEJ1fAnZGcvnG6OJVnLW/RhiOAQIQ8o 0lsyChf7s++AsLF5FGbt2KrjaTxzAAX25faImkKdvZcyhy5psBtQ95T5wz9JDYRE2hrKwPvtLYqSM ESIwABAhMCtIjqOaDVLqR5OWADnxnYy2R6SigB/fGPiIhFz9AjIIagIYpvdv3gncr5dkOitHBfQuD Wh3ofnuVwq0y+RKsV3lI+d++NiQxnWw8D1vn7kFWfVAkiRS2E0VdCzM6VzBgxSaO/F70TrwTVyNKF Nf+bAYOQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s3qya-000000069lB-1wJu; Mon, 06 May 2024 05:33:24 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1s3qyX-000000069in-2GOJ for linux-nvme@lists.infradead.org; Mon, 06 May 2024 05:33:23 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 711C868AFE; Mon, 6 May 2024 07:33:08 +0200 (CEST) Date: Mon, 6 May 2024 07:33:08 +0200 From: Christoph Hellwig To: Sagi Grimberg Cc: linux-nvme@lists.infradead.org, Christoph Hellwig , Keith Busch , Chaitanya Kulkarni Subject: Re: [PATCH] nvmet: make nvmet_wq unbound Message-ID: <20240506053308.GA5030@lst.de> References: <20240505103951.52413-1-sagi@grimberg.me> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240505103951.52413-1-sagi@grimberg.me> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240505_223321_740917_50F8D380 X-CRM114-Status: GOOD ( 16.78 ) 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 On Sun, May 05, 2024 at 01:39:51PM +0300, Sagi Grimberg wrote: > From: Sagi Grimberg > > When deleting many controllers one-by-one, it takes a very > long time as these work elements may serialize as they are > scheduled on the executing cpu instead of spreading. In general > nvmet_wq can definitely be used for long standing work elements > so its better to make it unbound regardless. This looks sensible, thanks. > While we are at it, expose it via sysfs to allow cpumask > control of this workqueue if a user wants to modify it. This on the other looks very questionable to me. It needs a way better justification and should be split into a separate patch if we really need it.