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=-8.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 1F73DC433E2 for ; Sun, 30 Aug 2020 11:30:39 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DDA09207DA for ; Sun, 30 Aug 2020 11:30:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dYmTJVFJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DDA09207DA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=containers-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id B1EEB85F6D; Sun, 30 Aug 2020 11:30:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id IgZ9sCnWhTe5; Sun, 30 Aug 2020 11:30:36 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id ED30985E14; Sun, 30 Aug 2020 11:30:35 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id D55CDC07FF; Sun, 30 Aug 2020 11:30:35 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id C35C4C0051 for ; Sun, 30 Aug 2020 11:30:34 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id AE202852D5 for ; Sun, 30 Aug 2020 11:30:34 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3QWDbAjDTP0j for ; Sun, 30 Aug 2020 11:30:34 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from us-smtp-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) by fraxinus.osuosl.org (Postfix) with ESMTPS id D080D85239 for ; Sun, 30 Aug 2020 11:30:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598787031; 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=ETh2SfT4KHd+5n3USTDSMP5uiOB3sVlZ/3ww+QanKH8=; b=dYmTJVFJZ+XIxva4R7R+LrIjs4o2Ai2rF9n0c13hRLvooEC5ZW/iALF/l6UvovUSwiLYaU P4mzdaELSJ5QHP6mDgo/XR8CUlR2v3IdAUoO13qjwi0rGU4QEvKIC/nhu8A6NGjfw2oh3N ZlC3MZRFwtrQOhx7WKm5VD+9PAN9XLU= 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-3-hz1v0BwXPy6kfSE3UYxG2A-1; Sun, 30 Aug 2020 07:30:27 -0400 X-MC-Unique: hz1v0BwXPy6kfSE3UYxG2A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DB5A0189E628; Sun, 30 Aug 2020 11:29:55 +0000 (UTC) Received: from localhost (ovpn-112-59.ams2.redhat.com [10.36.112.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 950007838E; Sun, 30 Aug 2020 11:29:54 +0000 (UTC) From: Giuseppe Scrivano To: Sargun Dhillon Subject: Re: Overlayfs @Plumbers References: <87tuwmiy4j.fsf@x220.int.ebiederm.org> <20200828155849.k46uk3x63aio3g3o@yavin.dot.cyphar.com> Date: Sun, 30 Aug 2020 13:29:51 +0200 In-Reply-To: (Sargun Dhillon's message of "Sat, 29 Aug 2020 08:40:36 -0700") Message-ID: <87imd09xsg.fsf@redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Cc: Linux Containers , "Eric W. Biederman" , overlayfs X-BeenThere: containers@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux Containers List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: containers-bounces@lists.linux-foundation.org Sender: "Containers" Hi Sargun, Sargun Dhillon writes: Q> On Fri, Aug 28, 2020 at 8:59 AM Aleksa Sarai wrote: >> >> On 2020-08-28, Eric W. Biederman wrote: >> > Amir Goldstein writes: >> > >> > > Hi Guys, >> > > >> > > It's been nice to virtually meet with you yesterday. >> > > Some of you wanted to follow up on overlayfs related issues. >> > > >> > > If you want to discuss, try to find me in one of the >> > > https://meet.2020.linuxplumbersconf.org/hackrooms >> > > today between 16:00-17:00 UTC >> > > (No need to enter the room to see who's inside) >> > > >> > > If those times do not work for you, contact me and we can try >> > > to schedule another time. >> > >> > Did this conversation wind up happening? Do we need to reschedule? >> >> This conversation already happened in a Hackroom on Tuesday. I'm not >> sure if the Hackrooms will have their recordings published, so maybe >> Amir can post any of the takeaways we had? >> >> -- >> Aleksa Sarai >> Senior Software Engineer (Containers) >> SUSE Linux GmbH >> > > I unfortunately missed this conversation. I wanted to bring up OverlayFS, and > ephemeral upper dirs. We use overlayfs with Docker containers, and we waste > a lot of time on writing things back to disk. > > We're not so peeved about the fact that OVL does any sync operations, as that's > what our users have been used to. The big problem is on unmount, ovelfs decides > syncing the upperdirs is a good idea. IIRC, this regression was > introduced somewhere > in the 4.X series. > > We've been carrying a patch to short-circuit this behaviour for a while now: > https://github.com/Netflix-Skunkworks/linux/commit/edb195d9b73cc22d095078010a14a690f41ee253 > > I know that this behaviour (and any behaviour that short-circuits > O_SYNC / FUA is > technically "wrong", but in this case, can we make an exception? I originally > thought about using device mapper to remove the FUA bit from all BIOs, but it > turns out that my underlying storage *always* persists data to disk, > so every write > takes...a long time. > > Amir, what's your take? we are having the same issue when building images. Would the following patch be helpful? https://www.spinics.net/lists/linux-unionfs/msg08267.html Regards, Giuseppe _______________________________________________ Containers mailing list Containers@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/containers