From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752714Ab2FMJ1J (ORCPT ); Wed, 13 Jun 2012 05:27:09 -0400 Received: from audible.transient.net ([216.254.12.79]:55055 "HELO audible.transient.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752238Ab2FMJ1H (ORCPT ); Wed, 13 Jun 2012 05:27:07 -0400 Date: Wed, 13 Jun 2012 09:27:03 +0000 From: Jamie Heilman To: "J. Bruce Fields" , "J. Bruce Fields" , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: RPC: fragment too large with transition to 3.4 Message-ID: <20120613092703.GA4701@cucamonga.audible.transient.net> Mail-Followup-To: "J. Bruce Fields" , "J. Bruce Fields" , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org References: <20120610090342.GA5076@cucamonga.audible.transient.net> <20120611161425.GF31109@pad.fieldses.org> <20120612101339.GB30293@cucamonga.audible.transient.net> <20120612111802.GI31109@pad.fieldses.org> <20120612123644.GA16430@fieldses.org> <20120613060627.GA11421@cucamonga.audible.transient.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120613060627.GA11421@cucamonga.audible.transient.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jamie Heilman wrote: > It's looking like my issues with "RPC: fragment too large" may be > something else entirely at this point, I've noticed other weird > network behavior that I'm gonna have to try to isolate before I keep > blaming nfs changes. Though for some reason my > /proc/fs/nfsd/max_block_size ends up only 128KiB w/3.4 where it was > 512KiB w/3.3. OK, I get it now. 32-bit PAE system w/4G of RAM (minus a chunk for the IGP video etc.) for my NFS server, and the max_block_size calculation changed significantly in commit 508f92275624fc755104b17945bdc822936f1918 to account for rpc buffers only being in low memory. That means whereas in 3.3 the math came out to having a target size of roughly 843241 my new target size in 3.4 is only 219959-ish, so choosing 128KiB is understandable. The problem was that all my clients had negotiated their nfs mounts against the v3.3 value of 512KiB, and when I rebooted into 3.4... they hit the wall attempting larger transfers and become uselessly stuck at that point. If I remount everything before doing any large transfers, then it negotiates a lower wsize and things work fine. So everything is working as planned I suppose... the transition between 3.3 and 3.4 is just a bit rough. -- Jamie Heilman http://audible.transient.net/~jamie/