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Date: Tue, 02 Dec 2014 17:25:02 -0600
From: Mark Kane <mark@kane.mn>
To: Freddie Cash <fjwcash@gmail.com>
Subject: Re: ZFS available space difference between 10.0 and 10.1
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On 2014-12-02 01:19, Freddie Cash wrote:
> IIUC, ZFS now reserves 3% of pool space for administrative purposes 
> (namely
> to be able to delete things when "pool is full").
> 
> So a pool imported on 10.0 will show more available space than a pool
> imported on 10.1.

Thanks Freddie. I had looked through the 10.1 release notes and UPDATING 
for any changes in how ZFS reserves space, but did not note anything 
that looked relevant. Appreciate the info.

It probably isn't super common to run pools so close to capacity like 
this one is (being used for temporary storage from a failed raidz), but 
if this is a known change that affects existing pools it would be great 
to have it in the release notes as it has the potential to break 
existing pools/filesystems in some cases :).

Thanks again,

-Mark