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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 4F17BC433E1 for ; Thu, 13 Aug 2020 15:11:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33F0B20791 for ; Thu, 13 Aug 2020 15:11:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726745AbgHMPL2 (ORCPT ); Thu, 13 Aug 2020 11:11:28 -0400 Received: from mx2.suse.de ([195.135.220.15]:58266 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726131AbgHMPL2 (ORCPT ); Thu, 13 Aug 2020 11:11:28 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 44713ACF9; Thu, 13 Aug 2020 15:11:49 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 6EAF0DA6EF; Thu, 13 Aug 2020 17:10:24 +0200 (CEST) Date: Thu, 13 Aug 2020 17:10:24 +0200 From: David Sterba To: Nikolay Borisov Cc: Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH 00/23][v4] Change data reservations to use the ticketing infra Message-ID: <20200813151024.GL2026@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Nikolay Borisov , Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com References: <20200721142234.2680-1-josef@toxicpanda.com> <121b9dab-888b-4be3-30bf-5719b9017014@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <121b9dab-888b-4be3-30bf-5719b9017014@suse.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Wed, Jul 22, 2020 at 11:35:15AM +0300, Nikolay Borisov wrote: > > > On 21.07.20 г. 17:22 ч., Josef Bacik wrote: > > v3->v4: > > - Rebased onto a recent misc-next, slight fixup because of commenting around the > > flush states. > > > > v2->v3: > > - Rebased onto a recent misc-next > > > > v1->v2: > > - Adjusted a comment in may_commit_transaction. > > - Fixed one of the intermediate patches to properly update ->reclaim_size. > > > > We've had two different things in place to reserve data and metadata space, > > because generally speaking data is much simpler. However the data reservations > > still suffered from the same issues that plagued metadata reservations, you > > could get multiple tasks racing in to get reservations. This causes problems > > with cases like write/delete loops where we should be able to fill up the fs, > > delete everything, and go again. You would sometimes race with a flusher that's > > trying to unpin the free space, take it's reservations, and then it would fail. > > > > Fix this by moving the data reservations under the metadata ticketing > > infrastructure. This gets rid of that problem, and simplifies our enospc code > > more by consolidating it into a single path. Thanks, > > > > Josef > > > > I've gone through the series again and it looks good. However, > btrfs_alloc_data_chunk_ondemand no longer allocates a data chunk but > simply tries to reserve the requested data space. This means this series > needs another patch giving it a more becoming name, something like > btrfs_(alloc|reserve)_data_space or some such ? Yes please, this could be confunsing as allocation and reservation are different things.