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=-7.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 65730C433FE for ; Thu, 3 Dec 2020 18:52:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03872207AD for ; Thu, 3 Dec 2020 18:52:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726885AbgLCSvv (ORCPT ); Thu, 3 Dec 2020 13:51:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725973AbgLCSvu (ORCPT ); Thu, 3 Dec 2020 13:51:50 -0500 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B590FC061A4E for ; Thu, 3 Dec 2020 10:51:10 -0800 (PST) Received: by fieldses.org (Postfix, from userid 2815) id 0289C6F5E; Thu, 3 Dec 2020 13:51:10 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org 0289C6F5E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1607021470; bh=On0cocyPm5XBAlbAfaHwqvtq06p6jvVhxIbij+bxQu4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Zror/5wohwl8C4kaHqmUv1AI/WDS32NK0BTlVzvWBJbOXMV42KL45SqeSNZtVkY/I cs5YNu5Ryj79qv8MSMLYZxSBxdVquFUKRt+UDUJLespgfsc0YMPGD+2yamagUA1coS Chxvvv9cEmnKmhF5xkmYeXQ71CkKphVhJneicg54= Date: Thu, 3 Dec 2020 13:51:09 -0500 From: bfields To: Daire Byrne Cc: Trond Myklebust , linux-cachefs , linux-nfs Subject: Re: Adventures in NFS re-exporting Message-ID: <20201203185109.GB27931@fieldses.org> References: <943482310.31162206.1599499860595.JavaMail.zimbra@dneg.com> <279389889.68934777.1603124383614.JavaMail.zimbra@dneg.com> <635679406.70384074.1603272832846.JavaMail.zimbra@dneg.com> <20201109160256.GB11144@fieldses.org> <1744768451.86186596.1605186084252.JavaMail.zimbra@dneg.com> <1055884313.92996091.1606250106656.JavaMail.zimbra@dneg.com> <20201124211522.GC7173@fieldses.org> <932244432.93596532.1606324491501.JavaMail.zimbra@dneg.com> <1403656117.98163597.1606998035261.JavaMail.zimbra@dneg.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1403656117.98163597.1606998035261.JavaMail.zimbra@dneg.com> User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Thu, Dec 03, 2020 at 12:20:35PM +0000, Daire Byrne wrote: > Just a small update based on the most recent patchsets from Trond & > Bruce: > > https://patchwork.kernel.org/project/linux-nfs/list/?series=393567 > https://patchwork.kernel.org/project/linux-nfs/list/?series=393561 > > For the write-through tests, the NFSv3 re-export of a NFSv4.2 server > has trimmed an extra GETATTR: > > Before: originating server <- (vers=4.2) <- reexport server - (vers=3) > <- client writing = WRITE,COMMIT,GETATTR .... repeating > > After: originating server <- (vers=4.2) <- reexport server - (vers=3) > <- client writing = WRITE,COMMIT .... repeating > > I'm assuming this is specifically due to the "EXPORT_OP_NOWCC" patch? Probably so, thanks for the update. > All other combinations look the same as before (for write-through). An > NFSv4.2 re-export of a NFSv3 server is still the best/ideal in terms > of not incurring extra metadata roundtrips when writing. > > It's great to see this re-export scenario becoming a better supported > (and performing) topology; many thanks all. I've been scratching my head over how to handle reboot of a re-exporting server. I think one way to fix it might be just to allow the re-export server to pass along reclaims to the original server as it receives them from its own clients. It might require some protocol tweaks, I'm not sure. I'll try to get my thoughts in order and propose something. --b.