From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefan Priebe <s.priebe@profihost.ag>
Subject: 10 times higher disk load with btrfs
Date: Mon, 05 Jan 2015 19:36:37 +0100
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Hi devs,

while btrfs is now declared as stable ;-) i wanted to retest btrfs on 
our production cluster on 2 out of 54 osds. So if they crash it doesn't 
hurt.

While if those OSDs run XFS have spikes of 20MB/s every 4-7s. The same 
OSDs after formatting them with btrfs have spikes of 190MB/s every 4-7s.

Why does just another filesystem raises the disk load by a factor of 10?

I'm running dumpling.

Greets Stefan