Re: iSCSI: draft 7: remove S bit and Status field from the Data-in PD

[Dave Sheehy <dbs@acropora.rose.agilent.com>]

Sorry for the delayed response, I was away from the office for most of last
week.

> > What are you trying to simplify?
> 
> Trying to simplify the receiver's data path by eliminating one of the
> two possible ways in which unsolicited data could arrive.

Eliminating immediate data doesn't accomplish that to any significant degree
hence my question.

> Eliminating the unsolicited PDUs is the WRONG choice because if you
> only have immediate data (data within the command PDU), you can must
> either a) make the allowable size of the command PDU relatively
> unbounded (to accomodate arbitrarily sized immediate data), which will
> break either framing mode b) severely limit the amount of unsolicited
> that can be sent, which makes unsolicited data useless.

I did not mean to imply that it was the RIGHT or the WRONG choice. John
Hufferd's post echoes my own thoughts on the matter quite well. Handling
unsolicited data PDUs at the target is a lot of work because they have
no target context and they arrive separately from the command. The handling
of immediate data is trivial in comparison.

> So, unsolicited data should be carried in a similar, if not identical
> way as regular data, tiled into multiple PDUs.

Then forget simplification because you aren't going to get it to any
significant degree.

Dave