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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 94BD9C2D0E7 for ; Thu, 26 Mar 2020 09:30:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 647F82076A for ; Thu, 26 Mar 2020 09:30:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qTbZo+d/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727719AbgCZJat (ORCPT ); Thu, 26 Mar 2020 05:30:49 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:39758 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727699AbgCZJat (ORCPT ); Thu, 26 Mar 2020 05:30:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=8tkb1WKEFrN4NlRAe9psjXHXdTX1+caSXEXvCYJZuU8=; b=qTbZo+d/BiYSGraIOZBdnZwHOT R7Tqb2N8iJWTVCo2OxAHOgKgKurnIsmbrmNZBX5pLIeuYfXEgRbs5lYNDBVqLOgA90vfjlAtpudEl MbUSlZ0ZRTbUdU+RMznpNzpGDDxbuIBX1mQ/OSfh8Jn2HYDrXd81HErvi2m/WFImfwJsn8bQDKm/I in06Rq09XujahHKR2AwFKFvswFsbi5wGBj/2xFzCKpo7WsyYBrcg0pv0HtvzOvgTiMMY+CrWYIeOu ej6mS5i/lx6nNNaRS/Fw6Trf5tv5faIEuiv00vbIAoD8KUKV8Nsn5+9c0QMA27GH081a19yBYSpoV gu2WIx2w==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jHOqf-000377-AA; Thu, 26 Mar 2020 09:30:49 +0000 Date: Thu, 26 Mar 2020 02:30:49 -0700 From: "hch@infradead.org" To: Damien Le Moal Cc: "hch@infradead.org" , "linux-block@vger.kernel.org" , Jens Axboe , "linux-scsi@vger.kernel.org" , "Martin K . Petersen" Subject: Re: [PATCH] block: all zones zone management operations Message-ID: <20200326093049.GB6478@infradead.org> References: <20200326043012.600187-1-damien.lemoal@wdc.com> <20200326072800.GA21082@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Mar 26, 2020 at 08:23:34AM +0000, Damien Le Moal wrote: > Open & Close all zones are indeed not super useful, at least on SMR drives. But > finishing all zones does have some benefit, namely the ability to quickly change > all incompletely written zones into "read-only" full zones. For drives with low > zone resources (open or active zones), this can be useful to recover zone > resources. Again, not so much on SMR drives, but this could come in handy for > ZNS drives with low zone resources (max open zones etc). What quantifies the "some benefit"? If you have an application that micro-manages the zone state it better knows what zones are open. But even if we want to add a finish all I'd rather wait for ZNS support to land and real use cases, as it sounds all rather dubious.