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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BD12C433E0 for ; Wed, 17 Jun 2020 12:06:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32F2220720 for ; Wed, 17 Jun 2020 12:06:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="HGvInCli" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726339AbgFQMGN (ORCPT ); Wed, 17 Jun 2020 08:06:13 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:46790 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725894AbgFQMGN (ORCPT ); Wed, 17 Jun 2020 08:06:13 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 05HBvR5V032179; Wed, 17 Jun 2020 12:03:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=to : cc : subject : from : message-id : references : date : in-reply-to : mime-version : content-type; s=corp-2020-01-29; bh=olGnmPODMTISYB7O5NdW1iJB91rNe+9YnXruLIPV6mM=; b=HGvInCliu7GXH43s3/EU/tg0m6miKIozPdwwMDaqhYUHU0MmR+hETsZKzNgNXPTLuCRd rymMo6974rJxsKa+v/B/AVHp6rC0frBdDKt9OBsrxuv5YVSsDteywIBUYlQxdei1ceKA 8jt4LprgW/tXHdXHTVwtzVyURR4tKi3Usb7n5v/5OwxDuh2Mu9Vp/RHdClbAAIVEbLcE TCaCCC2yDKoYL1sBz2qeo63u35hqrVTjitcPhT/uNkjxYyF3vup2nEMAJbLd4/vhlX+Q ZfG80YvmxtNsUnHYDKKSUJ+NTZ9OudzbXarzzgmC6wdfCNwmYqt8uBZ+cMXXzclid6dD 6Q== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2120.oracle.com with ESMTP id 31qg350qy3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 17 Jun 2020 12:03:44 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 05HBvd9l093547; Wed, 17 Jun 2020 12:01:43 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3020.oracle.com with ESMTP id 31q65xdnnt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 17 Jun 2020 12:01:43 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 05HC1bmp013213; Wed, 17 Jun 2020 12:01:38 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 17 Jun 2020 05:01:37 -0700 To: Christoph Hellwig Cc: Javier =?utf-8?Q?Gonz=C3=A1lez?= , Keith Busch , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, Damien Le Moal , Matias =?utf-8?Q?Bj=C3=B8rling?= , Sagi Grimberg , Jens Axboe , Hans Holmberg , Dmitry Fomichev , Ajay Joshi , Aravind Ramesh , Niklas Cassel Subject: Re: [PATCH 5/5] nvme: support for zoned namespaces From: "Martin K. Petersen" Organization: Oracle Corporation Message-ID: References: <20200615233424.13458-1-keith.busch@wdc.com> <20200615233424.13458-6-keith.busch@wdc.com> <20200616104142.zxw25txhsg2eyhsb@mpHalley.local> <20200617074328.GA13474@lst.de> Date: Wed, 17 Jun 2020 08:01:31 -0400 In-Reply-To: <20200617074328.GA13474@lst.de> (Christoph Hellwig's message of "Wed, 17 Jun 2020 09:43:28 +0200") MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9654 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 spamscore=0 phishscore=0 bulkscore=0 malwarescore=0 mlxscore=0 adultscore=0 suspectscore=1 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006170093 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9654 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 phishscore=0 mlxscore=0 clxscore=1011 malwarescore=0 impostorscore=0 adultscore=0 cotscore=-2147483648 lowpriorityscore=0 mlxlogscore=999 spamscore=0 suspectscore=1 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006170093 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org > Because Append is the way to go and we've moved the Linux zoned block > I/O stack to required it, Just to add some historical context: The first discussions about how to support block devices with a non-random write model in Linux happened maybe a decade ago. Drive vendors came to LSF/MM to solicit feedback on how Linux could support impending SMR devices. We spent a long time going over various approaches, including some that are similar to what is now being entertained as alternative to Append. The conclusion back then was that an Append-like model (tell-us-where-you-put-it) was the only reasonable way to accommodate these devices in Linux given how our filesystems and I/O stack worked. Consequently, I don't think it is at all unreasonable for us to focus on devices that implement that mode of operation in the kernel. This is exactly the that we as a community asked the storage industry to provide! -- Martin K. Petersen Oracle Linux Engineering