Re: [PATCH v20 00/12] Implement copy offload support

[Hannes Reinecke <hare@suse.de>]

On 6/4/24 06:32, Christoph Hellwig wrote:
> 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?
> 

The canonical example would be VM provisioning from a master copy.
That's not within a single block device, mind; that's more for copying 
the contents of one device to another.
But I wasn't aware that this approach is limited to copying within a 
single block devices; that would be quite pointless indeed.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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