Re: Creating backup snapshots (8 per filesystem) causes No space left on device?

[Marc MERLIN <marc@merlins.org>]

(replying on list)

On Sun, Apr 15, 2012 at 05:52:05PM +0200, Bart Noordervliet wrote:
> Hi Marc,
> 
> there's a known regression causing early "Out of space"-errors in
> kernel 3.3. A patch for stable has been queued I think, but it's not
> in 3.3.1 yet. So your best bet would be to either downgrade to 3.2 or
> use a 3.4-rc kernel. Otherwise you'd have to apply the patch in
> question yourself. It's been discussed on this list very recently.

I'll watch for 3.3.x updates (I see nothing in 3.3.2 yet), thanks.

Or is it just a matter of reverting this patch?
https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=5500cdbe14d7435e04f66ff3cfb8ecd8b8e44ebf
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index dc083f5..079e5a1 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4108,7 +4108,7 @@ static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
        num_bytes += div64_u64(data_used + meta_used, 50);
 
        if (num_bytes * 3 > meta_used)
-               num_bytes = div64_u64(meta_used, 3);
+               num_bytes = div64_u64(meta_used, 3) * 2;
 
        return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
 }


On Sun, Apr 15, 2012 at 10:19:30AM -0600, cwillu wrote:
> > but I can't get the filesystem show command to output anything useful:
> > gandalfthegreat:~# btrfs filesystem show /dev/mapper/cryptroot
> > Btrfs Btrfs v0.19
> 
> You need to run that as root.
 
That was run as root :)  '#'

Thanks for the replies,
Marc
-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/