T10/14-275r8 question

Gerry Houlder gerry.houlder at seagate.com
Tue Apr 14 12:08:24 PDT 2015

Formatted message: <a href="http://www.t10.org/cgi-bin/ac.pl?t=r&f=r1504141_f.htm">HTML-formatted message</a>

Kevin has noted this text in the Background Control model clause:
"A device server that supports Background Operation Control as described in
this subclause shall:
a) be a resource provisioned device as described in;
b) ..."
This restricts use of Background Control feature to resource provisioned
On Tue, Apr 14, 2015 at 1:52 PM, Joe Breher <Joe.Breher at hgst.com> wrote:
>  Kevin -
>  Great observation. I certainly think that BACKGROUND CONTROL has far
> wider applicability than that described in 14-275. While not at the
> proposal stage, I have been pondering some possibilities in that regard.
> There are many QoS improvement aspects of system behavior that can
> piggyback upon this mechanism.
>  While the model clause material in 14-275r8 4.32 "Background Operation
> Control" is written in terms of managing (over)provisioning, I see nothing
> elsewhere (e.g. the command description "5.99 BACKGROUND CONTROL command"
> preventing its use for other purposes. Have you found text within 14-275
> that prohibits the use of the BACKGROUND CONTROL command to anything other
> than the explicitly listed use case?
>  Lacking any specific prohibition upon such, my position would be that
> other uses can be described in the future that might control other forms of
> background operations by means of this mechanism. Such may require
> additional model text describing such usage of the BACKGROUND CONTROL
> command -- which is likely out of scope for this particular proposal.
> Though it may suggest a renaming of this particular model subclause to
> something more specific to the use cases within the proposal. Is this
> something we should do at this time?
>  Though your comment has prompted me to consider that 14-275r8 does not
> include all the necessary changes to SBC - such as the addition of the new
> commands to the "Commands for direct block access devices" Table 33 in
> sbc4r04.
>     Joe Breher
>  Storage Architecture Technologist
>  Standards Setting Organization
>  San Jose Research Center
>  HGST, a Western Digital company
>  (478) 2-Breher
>  (478) 227-3437
>  *This e-mail may contain confidential or legally privileged information
> of HGST. If you are not the intended recipient, please notify us
> immediately by responding to this e-mail and then deleting it from your
> system.*
>  On Apr 13, 2015, at 5:30 PM, Kevin D Butt <kdbutt at us.ibm.com> wrote:
>  Bill,
> Why does the storage intelligence restrict the Background Operation
> Control and Write Stream to only Resource Provisioned devices, when there
> could be value if it was used for both Thin and Thick Provisioning?
> Thanks,
> Kevin D. Butt
> SCSI Architect, Tape Firmware, CAMSS
> T10 Standards
> MS 6TYA, 9000 S. Rita Rd., Tucson, AZ 85744
> Tel: 520-799-5280
> Fax: 520-799-2723 (T/L:321)
> Email address: kdbutt at us.ibm.com
> http://www-03.ibm.com/servers/storage/

More information about the T10 mailing list