From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC PATCH v1 00/30] fs: inode->i_version rework and optimization
Date: Thu, 22 Dec 2016 00:45:49 -0800
Message-ID: <20161222084549.GA8833@infradead.org>
References: <1482339827-7882-1-git-send-email-jlayton@redhat.com>
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Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
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        linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org
To: Jeff Layton <jlayton@redhat.com>
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On Wed, Dec 21, 2016 at 12:03:17PM -0500, Jeff Layton wrote:
> Only btrfs, ext4, and xfs implement it for data changes. Because of
> this, these filesystems must log the inode to disk whenever the
> i_version counter changes. That has a non-zero performance impact,
> especially on write-heavy workloads, because we end up dirtying the
> inode metadata on every write, not just when the times change. [1]

Do you have numbers to justify these changes?