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Date: Mon, 13 Aug 2012 19:22:05 +0200
From: =?iso-8859-1?Q?Llu=EDs?= Batlle i Rossell <viric@viric.name>
To: linux-btrfs@vger.kernel.org
Subject: Defragmenting directories, compression
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Hello,

I've run "btrfs fi defrag /nix", a directory with only three subdirectories.

One of them, "/nix/store" has lots of contents. I expected the operation to last
very short, because I thought it was not recursive. But for what I see in
btrfs_root_defrag, it looks like it's recursive. And it takes long.

Additionally, defragmenting on a directory ignores the '-clzo' kind of
compression settings. And I wonder... as it works recursively, will it
*uncompress* all that big amount of data I have there in lots of files? All that
data has been filled with a "compress=lzo" mount option from long ago.

Additionally, 'btrfs fi defrag <directory>' seems to require root permisions,
while 'btrfs fi defrag <file>' does not, only file ownership (or writing
permision). Is this on purpose?

Regards,
Lluís.