copy offload for SMB?

Fri Feb 22 09:21:31 MST 2013

On 02/22/2013 09:36 AM, David Disseldorp wrote:
> On Fri, 22 Feb 2013 02:40:09 +0000
> "Liujun (A)" <liujun09 at huawei.com> wrote:
> 
>> I have wrote a test to test offload feature,  the is result is that Windows server 2012  does not support offload read (FSCTL_OFFLOAD_READ).
> 
> For the record, I think Windows Server 2k12 support for the new
> FSCTL_OFFLOAD_READ/WRITE SMBs is dependent on the underlying storage
> subsystem.

Yes.  It is akin in some ways to NDMP.

> It requires an advanced (expensive) storage array that handles
> POPULATE_TOKEN and WRITE_USING_TOKEN SCSI commands. See
> www.snia.org/sites/default/files2/SDC2011/presentations/monday/NealChristiansen_Win8FileSystemPerformance.pdf

The specifics are in the T10 docs, so it's now part of the SCSI spec.  It
should be possible to support this at the lower end.

Chris -)-----

-- 
"Implementing CIFS - the Common Internet FileSystem" ISBN: 013047116X
Samba Team -- http://www.samba.org/     -)-----   Christopher R. Hertel
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