From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-3.7 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 8F7131F8C8 for ; Wed, 8 Sep 2021 06:50:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242759AbhIHGvK (ORCPT ); Wed, 8 Sep 2021 02:51:10 -0400 Received: from verein.lst.de ([213.95.11.211]:38107 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238910AbhIHGvI (ORCPT ); Wed, 8 Sep 2021 02:51:08 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 9F14467373; Wed, 8 Sep 2021 08:49:58 +0200 (CEST) Date: Wed, 8 Sep 2021 08:49:58 +0200 From: Christoph Hellwig To: Junio C Hamano Cc: Neeraj Singh , "Neeraj K. Singh via GitGitGadget" , Git List , Johannes Schindelin , Jeff King , Jeff Hostetler , Christoph Hellwig , =?iso-8859-1?Q?=C6var_Arnfj=F6r=F0?= Bjarmason , "Neeraj K. Singh" Subject: Re: [PATCH v2 0/6] Implement a batched fsync option for core.fsyncObjectFiles Message-ID: <20210908064958.GA29073@lst.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tue, Sep 07, 2021 at 11:44:52PM -0700, Junio C Hamano wrote: > I doubt that fsyncObjectFiles is something we can reliably test in > CI, either with the new batched thing or with the original "when we > close one, make sure the changes hit the disk platter" approach. So > I am not sure what conclusion we should draw from such an experiment, > other than "ok, it compiles cleanly." After all, unless we cause > system crashes, what we thought we have written and close(2) would > be seen by another process that we spawn after that, with or without > sync, no? Basically yes. XFS on Linux has shutdown ioctls that allow to simulate that crash by shutting the file system down which really helps debugging that kind of code. A bunch of other file systems (ext4, f2fs) have also picked this up now (grep for {XFS,EXT4,F2FS}_IOC_SHUTDOWN).