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=-7.3 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 D6F6AC6379D for ; Wed, 25 Nov 2020 19:31:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3335420B1F for ; Wed, 25 Nov 2020 19:31:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fieldses.org header.i=@fieldses.org header.b="Vukxcyco" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728154AbgKYTbk (ORCPT ); Wed, 25 Nov 2020 14:31:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725776AbgKYTbj (ORCPT ); Wed, 25 Nov 2020 14:31:39 -0500 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2D2BC0613D4 for ; Wed, 25 Nov 2020 11:31:39 -0800 (PST) Received: by fieldses.org (Postfix, from userid 2815) id A6EDE6EAE; Wed, 25 Nov 2020 14:31:38 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org A6EDE6EAE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1606332698; bh=xyU4jzmIzeKYkiLfBQpm5G+31V0xWP28KnHvFM5AGeg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VukxcycoQhHQJMHQXGvaeyxRNYDHGGwlYl2BFom/k6v+VC0Vd34+CTbJpTH/We6ca 1TiC6WA6bxhIaxmiNbcavsUhsiELDcAG1uLFXU+he1v2YBIJdjauQKkfJVzL3qCsY7 Jf4MgIARIeAuoZzFqAIUwZZwNO/WvxTPLDtsIL3g= Date: Wed, 25 Nov 2020 14:31:38 -0500 From: bfields To: Daire Byrne Cc: Trond Myklebust , linux-cachefs , linux-nfs Subject: Re: Adventures in NFS re-exporting Message-ID: <20201125193138.GC7049@fieldses.org> References: <943482310.31162206.1599499860595.JavaMail.zimbra@dneg.com> <1188023047.38703514.1600272094778.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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <932244432.93596532.1606324491501.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 Wed, Nov 25, 2020 at 05:14:51PM +0000, Daire Byrne wrote: > Cool. I'm glad there are some notes for others to reference - this > thread is now too long for any human to read. The only things I'd > consider adding are: Thanks, done. > * re-export of NFSv4.0 filesystem can give input/output errors when the cache is dropped Looking back at that thread.... I suspect that's just unfixable, so all you can do is either use v4.1+ on the original server or 4.0+ on the edge clients. Or I wonder if it would help if there was some way to tell the 4.0 client just to try special stateids instead of attempting an open? > * a weird interaction with nfs client readahead such that all reads > are limited to the default 128k unless you manually increase it to > match rsize. > > The only other thing I can offer are tips & tricks for doing this kind > of thing over the WAN (vfs_cache_pressure, actimeo, nocto) and using > fscache. OK, I haven't tried to pick that out of the thread yet. --b.