From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josef Bacik Subject: Re: ENOSPC Regression Date: Fri, 11 Feb 2011 11:22:08 -0500 Message-ID: <20110211162208.GB2693@localhost.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-btrfs To: Mitch Harder Return-path: In-Reply-To: List-ID: On Fri, Feb 11, 2011 at 07:21:47AM -0600, Mitch Harder wrote: > I'm encountering premature ENOSPC issues recently where my Btrfs > testing partition will either prematurely return an ENOSPC, or lock up > the operations trying to access the partition. > > I have bisected the problem to this commit: > http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-unstable.git;a=commit;h=914ee295af418e936ec20a08c1663eaabe4cd07a > (Btrfs: pwrite blocked when writing from the mmaped buffer of the same page) > > I am encountering the problem on a small-ish 3.5 GB Btrfs partition. > I can replicate the problem with and without compression. I can also > replicate the problem with and without reformating the partition. > > For most operations I run on this partition, Btrfs is performing > without error. But when I compile openmotif-2.3.3 on a kernel that is > after the above referenced commit, I'll get either an ENOSPC error or > the partition locks up. > > When I encounter a lock-up issue, there are no errors in dmesg, and no > delayed processes are showing (unless I try to run an additional > operation on that partition, such as 'ls', which will subsequently > show up as delayed). However, the build process for openmotif-2.3.3 > appears frozen, and several processes related to the build are shown > as running, and will not even respond to 'kill -s 9 ' > > The partition only has about 500 MB of data when I encounter the > problems, and openmotif-2.3.3 typically only requires about 30-60 MB > to compile. > > However, running 'btrfs fi show' indicates that btrfs has attempted to > reserve all the space on the disk for data and metadata. When running > a kernel prior to the above referenced commit, btrfs will compile > openmotif-2.3.3 without needing to reserve much extra space on the > partition. > > Let me know if you would like any additional information or tests. Can you try my btrfs-work tree and see if you still have the same problem? Thanks, Josef