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From: Qu Wenruo <quwenruo@cn.fujitsu.com>
Subject: About per-file dedup flag
Message-ID: <56946E63.1040502@cn.fujitsu.com>
Date: Tue, 12 Jan 2016 11:09:23 +0800
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Hi all,

As some already know, we are implement btrfs in-band de-duplication.
And we already have a working and stable version internal.
But that's filesystem wide de-duplication.


Now we hope to add support to enable/disable dedup per-file.
Much like current NODATACOW/NOCOMPRESS for inode.


But we are not sure where to add such flag.
Here is our current ideas:

1) XATTR
Make a btrfs internal xattr, just like some btrfs prop.

2) inode flag, like FS_NOCOMP_FL
Although only btrfs is going to support in-band dedup, who knows
what will happen in future?

Any advice is welcomed.

Thanks,
Qu