RE: iSCSI: draft 7: remove S bit and Status field from the Data-i n PD U?

["Julian Satran" <Julian_Satran@il.ibm.com>]

Performance for the receiver is an issue - 3 reads instead of 2.
We agreed that we will examine the need for both immediate and
non-immediate unsolicited in the same execution
and this is by no means a major simplification.

Julo

Black_David@emc.com@ece.cmu.edu on 14-08-2001 03:57:56

Please respond to Black_David@emc.com

Sent by:  owner-ips@ece.cmu.edu


To:   John Hufferd/San Jose/IBM@IBMUS, ips@ece.cmu.edu
cc:
Subject:  RE: iSCSI: draft 7: remove S bit and Status field from the Data-i
      n PD U?



John,

I think you've taken a wrong turn.

> First, immediate and unsolicited separate Data PDUs are very valuable for
> situations where the Target is at distance from the Initiator.

Ok, that's fine.

> Second, thoughts of removing the immediate data seem not to be
> simplification, since all the information to tie the data to the command
is
> right there with the command.  That has got to be easier than matching up
> separate PDUs of data with the appropriate commands.

Actually, that was the point, since the logic for "matching up separate
PDUs of data with the appropriate commands" has to exist for inbound
Data PDUs already.  The slide I presented in London was about replacing
immediate data with an unsolicited data PDU immediately following the
command, thus removing the immediate data case in favor of reusing the
logic for dealing with separate Data PDUs.  Remember that this was
presented
as a simplification possibility.

Comments?
--David

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