From: Markus Trippelsdorf Subject: Re: torrent hash failures since 3.9.0-rc1 Date: Mon, 11 Mar 2013 21:13:34 +0100 Message-ID: <20130311201334.GA444@x4> References: <20130311171824.GA434@x4> <20130311191753.GA439@x4> <20130311194159.GB3579@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: Dave Jones , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Content-Disposition: inline In-Reply-To: <20130311194159.GB3579@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On 2013.03.11 at 15:41 -0400, Dave Jones wrote: > On Mon, Mar 11, 2013 at 08:17:53PM +0100, Markus Trippelsdorf wrote: > > On 2013.03.11 at 18:18 +0100, Markus Trippelsdorf wrote: > > > I get hash failures on "completed" torrents since 3.9.0-rc1 (Linux 3.8 > > > seems to be fine). What happens is that the torrents apparently complete > > > successfully. After reboot however the hash check fails and there are > > > missing (or corrupted) chunks. I've tested this with two different > > > clients (rtorrent and aria2c) and both are affected. So I think this > > > might be a filesystem issue. > > > > > > /dev/sda ext4 1.4T 666G 640G 51% /var > > > /dev/sda on /var type ext4 (rw,noatime,data=ordered) > > > > > > I use ECC memory (and there is nothing in the logs). > > > > To reproduce this issue just do the following: > > > > % wget http://torrents.linuxmint.com/torrents/linuxmint-12-gnome-cd-nocodecs-64bit.iso.torrent > > % rtorrent linuxmint-12-gnome-cd-nocodecs-64bit.iso.torrent > > (Wait until the torrent finishes) > > % sudo echo 3 > /proc/sys/vm/drop_caches > > (Rehash the torrent (Ctrl-R)) > > The torrent doesn't rehash successfully and a few hunks are > > missing/corrupted and need to be downloaded again. > > Worked fine for me on two separate machines. Could it be a network problem > perhaps ? If something is mangling the packet before it hits the disk, > that would explain it. What NIC do you use ? I normally use ATL1E, but I've dusted off my E100 and the issue is also reproducible on the Intel card. > Or maybe you could isolate it to a filesystem problem using something > like fsx ? I've found fsx on your homepage, but I've no idea on how to use this tool. Any pointers? -- Markus