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 2B507C433EF for ; Mon, 14 Mar 2022 07:42:26 +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=N7pECTiH+PvQ6mXNyMzjdE5aIVvYhlKCOVuopJAQ3dA=; b=R3+jUPfq5vR2inax+I4foUzoqT wFy3v6qn6sp/beDfynuLgyw3irbh7ZBCpvALcZ/P6PO8WjNQaOejrZv8HHT5tq04t51IsATlzWHws kjuBCmInZHfuP98tkSZd6HnOzgoPirTIEPmYy5ZUKICjsOYzKHS+WD2mkm/nuGQqsW+vQZ2mXjZIE vIhkEfl2rGwEmdAWKETmO62zh9l+AFyvqlANiZ5Kkt7LHqBmPyhLx+4o4cot1PuA4iRG924fqpOo7 pLf1mk+jMS/HRsNMGKkiUkiqAsFYvgiCiYSrc+5J8+pGXwyWP578YzZG/q293b5McyFfBR90b9jFm Wzh8h0UQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nTfLR-004BXN-Cf; Mon, 14 Mar 2022 07:42:21 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nTfG3-0048A4-5P for linux-nvme@lists.infradead.org; Mon, 14 Mar 2022 07:36:48 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 5F11D68AFE; Mon, 14 Mar 2022 08:36:44 +0100 (CET) Date: Mon, 14 Mar 2022 08:36:44 +0100 From: Christoph Hellwig To: Adam Manzanares Cc: Christoph Hellwig , Pankaj Raghav , Luis Chamberlain , Javier =?iso-8859-1?Q?Gonz=E1lez?= , kanchan Joshi , Jens Axboe , Keith Busch , Sagi Grimberg , Damien Le Moal , Matias =?iso-8859-1?Q?Bj=F8rling?= , "jiangbo.365@bytedance.com" , Pankaj Raghav , Kanchan Joshi , "linux-block@vger.kernel.org" , "linux-nvme@lists.infradead.org" Subject: Re: [PATCH 0/6] power_of_2 emulation support for NVMe ZNS devices Message-ID: <20220314073644.GB4204@lst.de> References: <20220308165349.231320-1-p.raghav@samsung.com> <20220310094725.GA28499@lst.de> <20220310173835.GB89599@bgt-140510-bm01> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220310173835.GB89599@bgt-140510-bm01> 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-20220314_003647_381446_F12A1E74 X-CRM114-Status: GOOD ( 13.27 ) 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 Thu, Mar 10, 2022 at 05:38:35PM +0000, Adam Manzanares wrote: > > Do these drives even support Zone Append? > > Should it matter if the drives support append? SMR drives do not support append > and they are considered zone block devices. Append seems to be an optimization > for users that want higher concurrency per zone. One can also build concurrency > by leveraging multiple zones simultaneously as well. Not supporting it natively for SMR is a major pain. Due to hard drives being relatively slow the emulation is somewhat workable, but on SSDs the serialization would completely kill performance.