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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 54835C433DB for ; Thu, 21 Jan 2021 23:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AC5123A5E for ; Thu, 21 Jan 2021 23:22:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725912AbhAUXV7 (ORCPT ); Thu, 21 Jan 2021 18:21:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbhAUXVt (ORCPT ); Thu, 21 Jan 2021 18:21:49 -0500 Received: from mail-lj1-x232.google.com (mail-lj1-x232.google.com [IPv6:2a00:1450:4864:20::232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D286DC0613D6 for ; Thu, 21 Jan 2021 15:21:03 -0800 (PST) Received: by mail-lj1-x232.google.com with SMTP id j3so4458111ljb.9 for ; Thu, 21 Jan 2021 15:21:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ucsc.edu; s=ucsc-google-2018; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=aGtXJ9JSGxtBc9xg3WRFWW32mVSM+OhKXJJnwYOIaH8=; b=rQ5kYcRgKxaek75+QtT2RaTkkaOSXLf7tvSbcjzY2DdFv8GXepB+qApS1tGx0cSB+T C1bO3TvVY/KuRpM6zK4zgVl91lpYDM4+TOT2bhqIsqcJEPQHyomWRu+uBcCyOGF2Zpnx hvlnTZz1lnNsfGJWjztmol9dymRW0GSCfAqdT6Lvoj0X/QSREG/arcGxmGDvDXLcM4h7 IggIQbxXdKD5KDoi2ojculnbBGt8HeeusoFoh0UXo7sfneScir/bBAq1I0EXGnBjr1Up xLSHd0KN31iPzjyeXyMs7XV3rSq8371KbFrBAYGOxsDTYcV7QhRchXEV2hNQR7wF7MKn iLxA== 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:content-transfer-encoding; bh=aGtXJ9JSGxtBc9xg3WRFWW32mVSM+OhKXJJnwYOIaH8=; b=nB22SALtzhOpi63nUM53mJo+n+cfQmOESv8kwE7W6NzQFCCkedbCr2Z/G+2iOIXqh5 /IAdo7RY1Cjdmx6srrnZpSV7cYeQx8qOPZstWGh93GQ9PtVaQ2vEe6FS6QF5Y2eZRi4l 901xvyBx9tuYcR3lyaxoEvKoMAt404SzJygD2sb7qS0L2WLsZMhAE5tXDMj7F7AoCoqV wSPS8haOXTW3YvRIw7d3fJX46RQ4chqB3lfcLbXWmntJ6sj0m4TGx3CqVPn2OL4ETVmI Logbb0geuEvbHU96QSWCnrwpMg+ehPWyPLKc7OSqGzASaXXDxfsgyie/E0jLm5MR5HwF eHLQ== X-Gm-Message-State: AOAM531Y9VhLdH2EfqmDugcd2C7idALE4jEB8b4+bbH/eodgWJxwY+OC GmVFLQJw0oQ6/1bMUaNvoZFUGvdDtHRYi5KTM9pRqA== X-Google-Smtp-Source: ABdhPJxgoZFXwC/GJMoLTVnJ9jo6wg5JBDrPwbNgtDIDaYGc88FWKCooZ+gkYoMaXwLPzopG+G/5NzzEWXMwXq/wcAY= X-Received: by 2002:a2e:b1d2:: with SMTP id e18mr54330lja.101.1611271262294; Thu, 21 Jan 2021 15:21:02 -0800 (PST) MIME-Version: 1.0 References: <20210121072202.120810-1-bianpan2016@163.com> <55045608-01cb-d5af-682b-5a213944e33d@kernel.dk> <474055ad-978a-4da5-d7f0-e2dc862b781c@lightnvm.io> <59a735f0-9fef-5e6d-f7eb-851e14a2883e@lightnvm.io> <586510be-5a56-5e99-6ee6-ee20031f166b@lightnvm.io> In-Reply-To: <586510be-5a56-5e99-6ee6-ee20031f166b@lightnvm.io> From: Heiner Litz Date: Thu, 21 Jan 2021 15:20:51 -0800 Message-ID: Subject: Re: [PATCH] lightnvm: fix memory leak when submit fails To: =?UTF-8?Q?Matias_Bj=C3=B8rling?= Cc: Jens Axboe , Pan Bian , linux-block@vger.kernel.org, Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org thanks, Matias, I am going to look out for dm-zap! On Thu, Jan 21, 2021 at 12:14 PM Matias Bj=C3=B8rling wrot= e: > > On 21/01/2021 20.49, Heiner Litz wrote: > > there are a couple more, but again I would understand if those are > > deemed not important enough to keep it. > > > > device emulation of (non-ZNS) SSD block device > > That'll soon be available. We will be open-sourcing a new device mapper > (dm-zap), which implements an indirection layer that enables ZNS SSDs to > be exposed as a conventional block device. > > > die control: yes endurance groups would help but I am not aware of any > > vendor supporting it > It is out there. Although, is this still important in 2021? OCSSD was > made back in the days where media program/erase suspend wasn't commonly > available and SSD controller were more simple. With today's media and > SSD controllers, it is hard to compete without leaving media throughput > on the table. If needed, splitting a drive into a few partitions should > be sufficient for many many types of workloads. > > finer-grained control: 1000's of open blocks vs. a handful of > > concurrently open zones > > It is dependent on the implementation - ZNS SSDs also supports 1000's of > open zones. > > Wrt to available OCSSD hardware - there isn't, to my knowledge, proper > implementations available, where media reliability is taken into account. > > Generally for the OCSSD hardware implementations, their UBER is > extremely low, and as such RAID or similar schemes must be implemented > on the host. pblk does not implement this, so at best, one should not > store data if one wants to get it back at some point. It also makes for > an unfair SSD comparison, as there is much more to an SSD than what > OCSSD + pblk implements. At worst, it'll lead to false understanding of > the challenges of making SSDs, and at best, work can be used as the > foundation for doing an actual SSD implementation. > > > OOB area: helpful for L2P recovery > > It is known as LBA metadata in NVMe. It is commonly available in many of > today's SSD. > > I understand your point that there is a lot of flexibility, but my > counter point is that there isn't anything in OCSSD, that is not > implementable or commonly available using today's NVMe concepts. > Furthermore, the known OCSSD research platforms can easily be updated to > expose the OCSSD characteristics through standardized NVMe concepts. > That would probably make for a good research paper. > >