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 1CCC81F8C6 for ; Thu, 26 Aug 2021 05:54:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232209AbhHZFz3 (ORCPT ); Thu, 26 Aug 2021 01:55:29 -0400 Received: from verein.lst.de ([213.95.11.211]:58108 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230313AbhHZFz2 (ORCPT ); Thu, 26 Aug 2021 01:55:28 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id C686F6736F; Thu, 26 Aug 2021 07:54:39 +0200 (CEST) Date: Thu, 26 Aug 2021 07:54:39 +0200 From: Christoph Hellwig To: Neeraj Singh Cc: Christoph Hellwig , Neeraj Singh via GitGitGadget , Git List , Johannes Schindelin , Jeff King , Jeff Hostetler , =?iso-8859-1?Q?=C6var_Arnfj=F6r=F0?= Bjarmason , "Neeraj K. Singh" Subject: Re: [PATCH 2/2] core.fsyncobjectfiles: batch disk flushes Message-ID: <20210826055439.GA17560@lst.de> References: <20210825053839.GA27037@lst.de> 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 Wed, Aug 25, 2021 at 10:40:53AM -0700, Neeraj Singh wrote: > I'd expect syncfs to suffer from the noisy-neighbor problem that Linus > alluded to on the big > thread you kicked off. It does. That being said I suspect in most developer workstation use cases it will still be a win. Maybe I'll look into implemeting it after your series lands. > If someone adds a more targeted bulk sync interface to the Linux > kernel, I'm sure Git could be > changed to use it. Maybe an fcntl(2) interface that initiates > writeback and registers completion with an > eventfd. That is in general very hard to do with how the VM-level writeback occurs. In the file system itself it could work much better, e.g. for XFS we write the log up to a specific sequence number and could notify when doing that.