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Date: Thu, 23 Apr 2026 07:11:42 +0200
From: Christoph Hellwig <hch@lst.de>
To: Niklas Cassel <cassel@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Carlos Maiolino <cem@kernel.org>,
	Damien Le Moal <dlemoal@kernel.org>,
	Hans Holmberg <hans.holmberg@wdc.com>,
	Johannes Thumshirn <johannes.thumshirn@wdc.com>,
	linux-xfs@vger.kernel.org
Subject: Re: [PATCH 1/2] xfs: expose the number of free zones in sysfs
Message-ID: <20260423051142.GA27929@lst.de>
References: <20260420135011.624587-4-cassel@kernel.org> <20260420135011.624587-5-cassel@kernel.org> <20260422060322.GC5391@lst.de> <aeii-qIyPawexQci@ryzen>
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On Wed, Apr 22, 2026 at 12:29:14PM +0200, Niklas Cassel wrote:
> You say that the usual way to expose stats is through 2)
> but e.g. nr_open_zones is exposed via 1), introduced in commit
> 62c89988dc19 ("xfs: expose the number of open zones in sysfs")
> (You are the author of that commit btw :))

nr_open_zones is important for applications as it tells them how many
different placement points we can have.  nr_free is really just
an implementation detail.