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Date: Sun, 22 Feb 2015 10:26:34 -0800
From: Robert White <rwhite@pobox.com>
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To: Bob Williams <linux@barrowhillfarm.org.uk>, linux-btrfs@vger.kernel.org
Subject: Re: scrub problem
References: <CABgvyo__OdS8N=Gwf-n58FTViyOi5ZWOcchud+Hmt1JfD8pNpw@mail.gmail.com> <54E7A128.1060603@barrowhillfarm.org.uk>
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On 02/20/2015 01:03 PM, Bob Williams wrote:
> /var/lib/btrfs/scrub.status.0b07b829-9a0e-44ab-89ee-14b36a45199e
>
> (the last bit of the filename is the filesystem uuid)
>
> Look for a line that ends with "finished:0" and change it to say
> "finished:1"

Why does this data item even exist? The filesystem/kernel should know 
whether a scrub is ongoing. Isn't is universally cheaper to do the 
single IOCTL to ask the kernel whether a scrub is ongoing compared to 
the open-and-parse of this file?