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Reply-To: waxhead@dirtcellar.net
To:     Btrfs BTRFS <linux-btrfs@vger.kernel.org>
From:   waxhead <waxhead@dirtcellar.net>
Subject: BTRFS subvolume RAID level
Message-ID: <494b0df1-2aab-5169-836d-e381498f64db@dirtcellar.net>
Date:   Thu, 28 Nov 2019 23:48:17 +0100
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Just out of curiosity....

What are the (potential) show stoppers for implementing subvolume RAID 
levels in BTRFS? This is more and more interesting now that new RAID 
levels has been merged (RAID1c3/4) and RAID5/6 is slowly inching towards 
usable status.

I imagine that RAIDc4 for example could potentially give a grotesque 
speed increase for parallel read operations once BTRFS learns to 
distribute reads to the device with the least waitqueue / fastest devices.