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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 AF308C35242 for ; Tue, 11 Feb 2020 19:19:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F7BD24676 for ; Tue, 11 Feb 2020 19:19:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="qwM6d5JT"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="qwM6d5JT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731593AbgBKTTE (ORCPT ); Tue, 11 Feb 2020 14:19:04 -0500 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:53102 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731591AbgBKTTD (ORCPT ); Tue, 11 Feb 2020 14:19:03 -0500 Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 5D2E48EE148; Tue, 11 Feb 2020 11:19:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1581448743; bh=BXU3TIG0j0QrJb5idUC/6y3sjEmyxsbL3NUmfSmqGgI=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=qwM6d5JTsKtlZ4lo3t97yVmlYcHSxFGhPwaP2uP07Yp36DmrXfUNyytT1BdCP0Z0e lA3YoOcxFeRd/U5+6f8lAHSSIln3i8PK42motZJq2bGR0ypuzFFvd5SmQNFsBDg1je Ge/4AQptXmp7BJjI6QO10WCFLgpl4XsAtfYaSqt0= Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EnRBXg5-50Hw; Tue, 11 Feb 2020 11:19:03 -0800 (PST) Received: from [10.252.1.156] (unknown [198.134.98.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id D24778EE0E0; Tue, 11 Feb 2020 11:19:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1581448743; bh=BXU3TIG0j0QrJb5idUC/6y3sjEmyxsbL3NUmfSmqGgI=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=qwM6d5JTsKtlZ4lo3t97yVmlYcHSxFGhPwaP2uP07Yp36DmrXfUNyytT1BdCP0Z0e lA3YoOcxFeRd/U5+6f8lAHSSIln3i8PK42motZJq2bGR0ypuzFFvd5SmQNFsBDg1je Ge/4AQptXmp7BJjI6QO10WCFLgpl4XsAtfYaSqt0= Message-ID: <1581448739.3519.5.camel@HansenPartnership.com> Subject: Re: [LSF/MM/BPF TOPIC] Multi-actuator HDDs From: James Bottomley To: Keith Busch , Muhammad Ahmad Cc: linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, Tim Walker Date: Tue, 11 Feb 2020 11:18:59 -0800 In-Reply-To: <20200210182645.GA2535@dhcp-10-100-145-180.wdl.wdc.com> References: <20200210182645.GA2535@dhcp-10-100-145-180.wdl.wdc.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, 2020-02-10 at 10:26 -0800, Keith Busch wrote: > On Mon, Feb 10, 2020 at 12:01:13PM -0600, Muhammad Ahmad wrote: > > For NVMe HDDs are namespaces the appropriate abstraction of the > > multiple actuators? > > This sounds closer to what "NVM Sets" defines rather than namespaces. > Section 4.9 from NVMe 1.4 spec has additional details if interested. I've got to say that since multi-actuator devices will always be spinning rust, bending NVMe concepts to fit them seems horribly wrong ... as does adding any rotational devices to NVMe: You just built a clean NVM stack ... let's not contaminate it. James