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Date: Tue, 4 Jun 2024 06:32:42 +0200
From: Christoph Hellwig <hch@lst.de>
To: Nitesh Shetty <nj.shetty@samsung.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Jonathan Corbet <corbet@lwn.net>, Alasdair Kergon <agk@redhat.com>,
	Mike Snitzer <snitzer@kernel.org>,
	Mikulas Patocka <mpatocka@redhat.com>,
	Keith Busch <kbusch@kernel.org>, Sagi Grimberg <sagi@grimberg.me>,
	Chaitanya Kulkarni <kch@nvidia.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH v20 00/12] Implement copy offload support
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On Mon, Jun 03, 2024 at 10:53:39AM +0000, Nitesh Shetty wrote:
> The major benefit of this copy-offload/emulation framework is
> observed in fabrics setup, for copy workloads across the network.
> The host will send offload command over the network and actual copy
> can be achieved using emulation on the target (hence patch 4).
> This results in higher performance and lower network consumption,
> as compared to read and write travelling across the network.
> With this design of copy-offload/emulation we are able to see the
> following improvements as compared to userspace read + write on a
> NVMeOF TCP setup:

What is the use case of this?   What workloads does raw copies a lot
of data inside a single block device?