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Date:   Thu, 12 Oct 2023 01:34:34 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Catherine Hoang <catherine.hoang@oracle.com>
Cc:     linux-xfs@vger.kernel.org
Subject: Re: [PATCH v3] xfs: allow read IO and FICLONE to run concurrently
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On Wed, Oct 11, 2023 at 06:08:45PM -0700, Catherine Hoang wrote:
> Clone operations and read IO do not change any data in the source file, so they
> should be able to run concurrently. Demote the exclusive locks taken by FICLONE
> to shared locks to allow reads while cloning. While a clone is in progress,
> writes will take the IOLOCK_EXCL, so they block until the clone completes.

FYI, the first two lines are too long for the normal commit log format.

Can you provide a justification for the change, i.e. worksloads for
which this matters, and what metrics are improved?