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=-3.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 237BBC388F9 for ; Wed, 21 Oct 2020 17:48:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0DA62242F for ; Wed, 21 Oct 2020 17:48:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="DVzkzBJt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2503718AbgJURsh (ORCPT ); Wed, 21 Oct 2020 13:48:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2503716AbgJURsh (ORCPT ); Wed, 21 Oct 2020 13:48:37 -0400 Received: from mail-ed1-x544.google.com (mail-ed1-x544.google.com [IPv6:2a00:1450:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31080C0613CF for ; Wed, 21 Oct 2020 10:48:37 -0700 (PDT) Received: by mail-ed1-x544.google.com with SMTP id l16so3471777eds.3 for ; Wed, 21 Oct 2020 10:48:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wz+eFQ9E3XaBY60yIiY6/7ACNu1JGiJC/eGXK+f1jPc=; b=DVzkzBJthtEEE9BytDByy1Zyi6AvIrMMfqilJKnpXorOKZpcoMkmRc0+51O1rnlt68 bMY0od0cPkgr22Fq/K+EKbRk9QUUZlKvr9mGhIHdkRS+RFdmguKEoaDMpwVT2MTekysU aICew+9IVF+RRyoiu/PaGJVFHpxpM2ZfnviDOpSraD9hqMuMque7/usM9pzF/eaK9iyi qZF3JdUTjmf2nLs5oVUYf43A1aDD3wYoYI9oxDRZY55ia14p0XqJNtzi/CDl0A92VIsH Ytn7i5HZw9HsfFtKjUgs2Sf+IlYn4ti3aGTMDIrNugvXoKAtZI0M50rVaCu67NNkO/yB jfiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wz+eFQ9E3XaBY60yIiY6/7ACNu1JGiJC/eGXK+f1jPc=; b=jOQmR3p0/j4ZSLDsR3I1jro1dHGaK5QnqlXXqQa9xQaCYWUUcGT3incGkLQ16/gnDk SnEw8wnzI+7vIYxqLd7lfrNKQPQ/2KEo6yauMYk7z0dGPSrvi9qUoMDiG9C/osUKOf8J ig7b7SiPUJpDPOZeLaxTBgimHfsYNIvcYMCcM1RlYljwFZoRcadtwqwlesQAxdbMSf6I s+S56siQPkXtpY1+KnCQE1xcgtmDYqrFgvSFLtFbNI/1IPeHIO9fI6UQbXEhiPj8HKrd YRpCyEdpPwhFAcf1V987uFw8Ic1f3bgl+D+nVPWnpMbu0chpyyP5KQC1kj5r2j2g2uLu D+Jw== X-Gm-Message-State: AOAM533AH58NiY7t9DzwzKj87MxJSk9M1sW5AwNHP/mzOXheW+TZ7j/e VGyADeh1pz5peWghQTaC3sDGBc/Gs5MkQJ93R05SXA== X-Google-Smtp-Source: ABdhPJyjfO8m3iOuqLFtlf+FomXd1BC4F7cQcApVrqZXlZQ1jUukEoyZcjOKoq++KT+r97hpdUtXqWK1yOAZ0wQ8O8o= X-Received: by 2002:a05:6402:31b3:: with SMTP id dj19mr4292662edb.210.1603302515911; Wed, 21 Oct 2020 10:48:35 -0700 (PDT) MIME-Version: 1.0 References: <20201012162736.65241-1-nmeeramohide@micron.com> <20201015080254.GA31136@infradead.org> In-Reply-To: From: Dan Williams Date: Wed, 21 Oct 2020 10:48:24 -0700 Message-ID: Subject: Re: [EXT] Re: [PATCH v2 00/22] add Object Storage Media Pool (mpool) To: "Nabeel Meeramohideen Mohamed (nmeeramohide)" Cc: Christoph Hellwig , "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "linux-mm@kvack.org" , "linux-nvdimm@lists.01.org" , "Steve Moyer (smoyer)" , "Greg Becker (gbecker)" , "Pierre Labat (plabat)" , "John Groves (jgroves)" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, Oct 21, 2020 at 10:11 AM Nabeel Meeramohideen Mohamed (nmeeramohide) wrote: > > On Tuesday, October 20, 2020 3:36 PM, Dan Williams wrote: > > > > What does Linux get from merging mpool? > > > > What Linux gets from merging mpool is a generic object store target with some > unique and beneficial features: I'll try to make the point a different way. Mpool points out places where the existing apis fail to scale. Rather than attempt to fix that problem it proposes to replace the old apis. However, the old apis are still there. So now upstream has 2 maintenance burdens when it could have just had one. So when I ask "what does Linux get" it is in reference to the fact that Linux gets a compounded maintenance problem and whether the benefits of mpool outweigh that burden. Historically Linux has been able to evolve to meet the scaling requirements of new applications, so I am asking whether you have tried to solve the application problem by evolving rather than replacing existing infrastructure? The justification to replace rather than evolve is high because that's how core Linux stays relevant.