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	Wed, 27 Jan 2016 03:48:21 -0500
Subject: Re: btrfs-progs 4.4 re-balance of RAID6 is very slow / limited to one
 cpu core?
To: Chris Murphy <lists@colorremedies.com>,
        "Austin S. Hemmelgarn" <ahferroin7@gmail.com>
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From: Christian Rohmann <crohmann@netcologne.de>
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Date: Wed, 27 Jan 2016 09:48:18 +0100
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On 01/26/2016 09:20 PM, Chris Murphy wrote:
> nyway,
> it seems reasonable to try a balance without the filters to see if
> that's a factor, because those filters are brand new in btrfs-progs
> 4.4. Granted, I'd expect they've been tested by upstream developers,
> but I don't know if there's an fstest for balance with these specific
> filters yet.

I have another box with 8 disks RAID6 on which I simply did a balance
with no newly added drives. Same issue ... VERY slow running balance
with IO nowhere near 100% utilization and many many days of runtime to
finish.


Regards

Christian