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Date:   Thu, 11 Nov 2021 16:05:39 +0100
From:   David Sterba <dsterba@suse.cz>
To:     Nikolay Borisov <nborisov@suse.com>
Cc:     linux-btrfs@vger.kernel.org
Subject: Re: [PATCH v2 0/3] x Balance vs device add fixes
Message-ID: <20211111150538.GF28560@twin.jikos.cz>
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On Mon, Nov 08, 2021 at 04:28:17PM +0200, Nikolay Borisov wrote:
> Here's v2 of the patchset allowinig to add a device if we have paused balanced.

I haven't figred out any problematic state. As the paused balance is
a note about the request filters and progress, restarting balance with a
new device will apply accordingly. The result will be of course
affected, eg. chunk layout or allocation order, but other than that I
think it's fine.

One remaining thing is to teach progs that there's a new state and how
it's compatible. This needs to mimic the logic in kernel. As it's a
simple change it can go to any release before the kernel changes get
released.