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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 79DB1C433E5 for ; Tue, 21 Jul 2020 13:51:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57A8B206E9 for ; Tue, 21 Jul 2020 13:51:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YTCvJpfe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726949AbgGUNve (ORCPT ); Tue, 21 Jul 2020 09:51:34 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:33267 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726506AbgGUNvd (ORCPT ); Tue, 21 Jul 2020 09:51:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595339492; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=yprAtR9XHlpKxtrX4jYo/Pn8Fvvc3FitPJ8aeq1QjJQ=; b=YTCvJpfed8w1ESKhKLgDHzNHk9yA5M4hyAspWlNurlWGhVGD6yF2aPIhoR1YX6fbJwrFN5 BWd93r6IQGfJKCyAfwxbHfCDCdD0kEkloaCYY9LPQwhPKda18615m0RK3gmbSG3cwGf5nZ WaWT3mzM3za2ICPe0P5J1Y4o12ZoYvE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-420--NV0K4yrM8CkWrY-Upp5Fg-1; Tue, 21 Jul 2020 09:51:28 -0400 X-MC-Unique: -NV0K4yrM8CkWrY-Upp5Fg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A71F918FF687; Tue, 21 Jul 2020 13:51:27 +0000 (UTC) Received: from horse.redhat.com (ovpn-116-14.rdu2.redhat.com [10.10.116.14]) by smtp.corp.redhat.com (Postfix) with ESMTP id 02B3D2DE6F; Tue, 21 Jul 2020 13:51:24 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id 8CED4223C1E; Tue, 21 Jul 2020 09:51:23 -0400 (EDT) Date: Tue, 21 Jul 2020 09:51:23 -0400 From: Vivek Goyal To: Miklos Szeredi Cc: Amir Goldstein , overlayfs , Giuseppe Scrivano , Daniel J Walsh , Steven Whitehouse , pmatilai@redhat.com, sandeen@redhat.com Subject: Re: [PATCH v4] overlayfs: Provide mount options sync=off/fs to skip sync Message-ID: <20200721135123.GA551452@redhat.com> References: <20200706161227.GB3107@redhat.com> <20200720161618.GD502563@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-unionfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org On Tue, Jul 21, 2020 at 03:15:55PM +0200, Miklos Szeredi wrote: > On Mon, Jul 20, 2020 at 6:16 PM Vivek Goyal wrote: > > > For building images containers folks need to sync upper layer. Their > > current plan is to use "syncfs upper/" because it is same as if overlay > > was mounted with sync=fs. But this syncs whole upper filesystem and > > not just upper of a particular overlayfs instance > > > > So idea was to provide sync=fs from the beginning and ask container > > folks to use this. So that in future if we can optimize sync=fs to > > sync selctive inodes, then container runtime will automatically > > benefit from it without any changes. It also reduces the chances > > of error on container runtime which fail to sync upper. Hence idea > > of sync=fs sounded appleaing to me. > > Not sure I understand the reason for sync=fs? Should it rather be > sync=shutdown? > > > > > Havid said that, I am open to dropping sync=fs for now, if you don't > > see the value at this point of time. > > At this point it doesn't add any usefulness, so let's just drop it. Ok, Will drop it. > > > > > > > Naming: I'm not at all convinced by any name having "sync" in it. I > > > think "sync=no" is about the implementation, not the functionality, > > > and so it's confusing. The functionality is better described by > > > "volatile" or "temporary". But I can live with sync=... if voted > > > down. > > > > I am fine with the name "volatile/temporary" for sync=off. > > How about needing "volatile" for all kinds of modes that reduce the > normal durability/integrity guarantees. Then additional "sync=foobar" > option to control the details? Sounds good. For now I will just implement "volatile" which is equivalent of sync=off. One can implement "volatile,sync=shutdown" in future if need be. Thanks Vivek