From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Sanders Subject: Re: btrfs hang in flush-btrfs-5 Date: Mon, 11 Jul 2011 22:21:21 +0100 Message-ID: References: <4E1B08FC.6030907@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" To: linux-btrfs@vger.kernel.org Return-path: List-ID: Josef Bacik wrote: > On 07/11/2011 07:40 AM, Jeremy Sanders wrote: >> Jeremy Sanders wrote: >> >>> Hi - I'm trying btrfs with kernel 2.6.38.8-32.fc15.x86_64 (a Fedora >>> kernel). I'm just doing a tar-to-tar copy onto the file system with >>> compress- force=zlib. Here are some traces of the stuck processes. >> >> I've managed to reproduce the hang using the latest btrfs from the >> repository. I had to remove some of the tracing lines to get it to >> compile under 2.6.38.8 and an ioctl which wasn't defined. Here is is >> where it is stuck: >> > > Hrm well that is just unlikely and hard to hit. Will you try this and > see if it helps you? Thanks, It's got quite a bit further past than where it got before and hasn't crashed yet. I will let you know when it has finished ok. I see that the btrfs-delalloc (rather than endio-write) thread is taking up 100% of CPU and the write speed seems to have dropped during the copying, however. The copy started with using endio-write fully on both cores and now is using dealloc a lot. Jeremy