Re: Online resize vs ENOSPC

[Hugo Mills <hugo-lkml@carfax.org.uk>]

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On Mon, Mar 09, 2009 at 10:31:41AM +0000, Hugo Mills wrote:
>    After an online resize, the filesystem reports its new size, but
> still runs out of space at the old size:
[...]
>    Unmounting and remounting the filesystem seems to make the new
> space available for use again.
> 
>    This is the second time I've had this happen to me now, so it seems
> to be more-or-less reproducible, although I haven't deliberately tried
> to trigger the behaviour yet.

   Just to confirm, I can indeed reproduce it trivially:

$ sudo lvcreate scratch -n testresize -L 5G
$ sudo mkfs.btrfs /dev/scratch/testresize
$ sudo mount /dev/scratch/testresize /mnt
$ sudo chmod ug+w /mnt
$ sudo chown hrm. /mnt
$ cd /mnt
$ dd if=/dev/zero of=foo.txt bs=1M count=4096
$ sudo lvextend scratch/testresize -L 9G
$ sudo btrfsctl -r 9G /mnt
$ dd if=/dev/zero of=foo2.txt bs=1M count=4096

and I get an out-of-space error within a few hundred blocks.

$ cd ..
$ sudo umount /mnt
$ sudo mount /dev/scratch/testresize /mnt
$ cd /mnt
$ dd if=/dev/zero of=foo2.txt bs=1M count=4096

and then I can write the full 4G of data.

   Hugo.

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=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
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