Minutes of X3T10 SCSI Working Group Meeting - May 7-8, 1996

Lohmeyer, John JLOHMEYE at cossymwest.co.symbios.com
Tue May 14 13:51:00 PDT 1996

* From the SCSI Reflector, posted by:

Minutes of SCSI Working Group meeting in Ft. Lauderdale, FL   

Accredited Standards Committee*
X3, Information Technology
                                              Doc. No.: X3T10/96-167r0
                                                  Date: May 14, 1996
                                             Ref. Doc.:
                                              Reply to: John Lohmeyer

To:       Membership of X3T10

From:     Ralph Weber, Secretary X3T10
          Larry Lamers, Vice-chair X3T10
          John Lohmeyer, Chair X3T10

Subject:  Minutes of X3T10 SCSI Working Group Meeting
          Ft. Lauderdale, FL -- May 7-8, 1996


1. Opening Remarks

2. Approval of Agenda

3. Attendance and Membership

4. Physical Topics
  4.1 SPI Amendment (96-130) [Johansson]
  4.2 SPI-2 Hot Plugging [Ham]
  4.3 Arbitration Fairness [Lohmeyer]
  4.4 SPI-2 Document Strategy
  4.5 Clarification of When Parity Is Valid (96-162r0) [Penokie]

5. Protocol Topics
  5.1 Problem with Non-interlocked Busses (96-173r0) [Monia]
  5.2 SIP and Command Queuing (96-112r0) [McGrath]
     5.2.1 SAM and Task Management (96-170r0) [Johansson]
  5.3 SAM-2 Changes (96-169r0) [Monia]
  5.4 Tape Support on FC-AL (Reflector Messages) [Hagerman]

6. Command Set Topics
  6.1  Resolution  of the SCSI-3 Primary Commands (SPC)  Forwarding
     Comments [Weber]
  6.2 Review of SCSI-3 Enclosure Services (SES) [Snively]
  6.3 Clarification of sleep mode (96-141r1) [Penokie]
  6.4 Programmable Capacity Revisited (96-171r0) [Houlder]
  6.5 SCSI-3 Block Commands (SBC) Review [Milligan]
  6.6 SCC-2 Discussion [Penokie]
  6.7 Security Erase [Schultz/Lohmeyer]
  6.8 MMC-2 and/or Additional CD-ROM Command Set Project (X3T13/96-
     009) [Milligan]
  6.9 Additional XOR bit [Milligan, Reflector]

7. Other Topics
  7.1 Greater than 8GB Technical Report [Penman]
  7.2 High Availability SCSI Profile (96-151r1) [Hagerman]
  7.3 STA Liaison [McGrath]
  7.4 Normative References

8. Meeting Schedule

9. Adjournment

                          Results of Meeting

1.   Opening Remarks

John Lohmeyer, the X3T10 Chair, called the meeting to order at 9:05
a.m., Tuesday May 7, 1996.  He thanked Norm Harris of Adaptec for
hosting the meeting.

As is customary, the people attending introduced themselves and a copy
of the attendance list was circulated.  Copies of the draft agenda and
general information on X3T10 were made available to those attending.

2.   Approval of Agenda

The draft agenda was approved with the following additions:

     4.2 SPI-2 Hot Plugging [Ham]
     4.3 Arbitration Fairness [Lohmeyer]
     4.4 SPI-2 Document Strategy
     4.5 Clarification of When Parity Is Valid [Penokie]
     5.2.1 SAM and Task Management [Johansson]
     6.9 Additional XOR bit [Milligan, Reflector]
     7.3 STA Liaison [McGrath]
     7.4 Normative References

3.   Attendance and Membership

 Attendance at working group meetings does not count toward minimum
 attendance requirements for X3T10 membership.  Working group meetings
 are open to any person or organization directly and materially
 affected by X3T10's scope of work.

 The following people attended the meeting:

         Name          S        Organization         Electronic Mail   
 ---------------------- -- -------------------------   
Mr. Norm Harris        P  Adaptec, Inc.   
            nharris at eng.adaptec.com
Mr. Lawrence J. Lamers A  Adaptec, Inc.             ljlamers at aol.com
Mr. Tak Asami          A# Adaptec, Inc.             asami at itc.adaptec.com
Mr. Edward Fong        P  Amdahl Corp.   
             esf10 at amail.amdahl.com
Mr. George Preputnick  V  AMP, Inc.                 gpreputn at amp.com
Mr. Borden Moller      V  CMD Technology            borden at cmd.com
Mr. Peter Johansson    P  Congruent Software, Inc.  pjohansson at aol.com
Mr. Charles Monia      P  Digital Equipment Corp.   monia at shr.dec.com
Mr. William Dallas     A# Digital Equipment Corp.   
  dallas at wasted.enet.dec.com
Mr. Douglas Hagerman   A# Digital Equipment Corp.   
  hagerman at starch.enet.dec.
Mr. Ralph O. Weber     P  ENDL Associate            roweber at acm.org
Mr. Edward Lappin      P  Exabyte Corp.             tedl at exabyte.com
Mr. Gary R. Stephens   P  FSI Consulting Services   6363897 at mcimail.com
Mr. Stephen Holmstead  P  Hewlett Packard Co.   
      stephen at mail.boi.hp.com
Mr. George Penokie     P  IBM Corp.   
                gop at rchvmp3.vnet.ibm.com
Mr. Dennis Moore       P  KnowledgeTek, Inc.        dmoore at netcom.com
Mr. Robert Bellino     A# Madison Cable Corp.   
      robert_bellino at madisonusa

Mr. Pete McLean        P  Maxtor Corp.   
             pete_mclean at maxtor.com
Mr. Edward A. Gardner  P  Ophidian Designs          gardner at acm.org
Mr. Skip Jones         P  QLogic Corp.              sk_jones at qlc.com
Mr. James McGrath      P  Quantum Corp.             JMCGRATH at QNTM.COM
Mr. Gene Milligan      P  Seagate Technology        Gene_Milligan at notes.
Mr. Gerald Houlder     A  Seagate Technology        Gerry_Houlder at notes.
Mr. Dave Guss          P  Silicon Systems, Inc.   
    dave.guss at tus.ssi1.com
Mr. Robert N. Snively  P  Sun Microsystems Computer   
bob.snively at eng.sun.com
Mr. John Lohmeyer      P  Symbios Logic Inc.   
       john.lohmeyer at symbios.com
Mr. Rod DeKoning       A  Symbios Logic Inc.   
       rod.dekoning at symbios.com
Mr. Pete Tobias        A  Tandem Computers   
         tobias_pete at tandem.com
Mr. Kenneth J. Hallam  P  UNISYS Corporation   
       ken.hallam at mv.unisys.com
Mr. Paul D. Aloisi     P  Unitrode Integrated       Aloisi at uicc.com
Mr. Douglas C.         V  Wolf, Greenfield, and     ddoskocil at wgslaw.com
Doskocil                  Sacks
Mr. Tom Sullivan       V  Wolf, Greenfield, and

32 People Present

Status Key:  P    -  Principal
             A,A# -  Alternate
             O    -  Observer
             L    -  Liaison
             V    -  Visitor

4.   Physical Topics

     4.1  SPI Amendment (96-130) [Johansson]

John described the sequence of events by which ANSI has "thrown" SPI
into a limited public review covering just the figures that changed as
a result of the drafting standards change (see the minutes from the
March Plenary meeting, X3T10/96-139).  He noted that the additional
public review will delay publication of SPI without offering X3T10 the
opportunity to correct the other known errors.

There was a brief discussion regarding how best to proceed with
processing the amendment.  It was decided to attempt to take formal
action on the amendment following this month's plenary meeting.

     4.2  SPI-2 Hot Plugging [Ham]

John reported that Bill Ham has determined that SPI-2, LVD cannot
support hot plugging case 4 (changes in configuration without first
suspending I/O traffic on the bus).  Since this issue was discussed
during the SPI-2 Working Group meeting, there was very little
discussion of John's report.

     4.3  Arbitration Fairness [Lohmeyer]

John introduced the problem of arbitration fairness in configurations
with large numbers of drives on a single parallel bus.  Low priority
drives get starved for bus access.  John described an IBM technical
report on fairness that George later turned into a X3T9.2 proposal (89-
061r0).  Questions were raised regarding whether IBM patented the
algorithm described in their technical report.  George agreed to
determine whether the algorithm was patented.  The following day,
George reported that the IBM fairness algorithm had been published
rather than patented.  Larry agreed to redistribute 89-061r0 as 96-
172r0 in mailing #3.

John summed up by say that in large configurations, such as those
envisioned in EPI, a fairness algorithm will be necessary.  Jim
McGrath requested a description of the requirements of a fairness
algorithm.  He suggested that some of the existing Disconnect
Reconnect Mode Page controls might be used to produce fairness.  After
some discussion, it became evident that Jim's requirements were for an
isochronous data transfer mechanism, which may need an entirely
separate mechanism.

     4.4  SPI-2 Document Strategy

John described the original proposal to have SPI-2 supersede all
previous parallel physical definitions: SPI, Fast-20, etc.  He then
described the proposed change to having SPI-2 contain only new work.
Gene Milligan requested that a detailed outline of the planned
contents of SPI-2 (as envisioned today).  He was concerned about how
the known warts in SPI can be dealt with.  John explained the process
by which he believes the SPI document can be corrected, including
working a corrected SPI through ISO.

John, Larry, and Skip Jones discussed the pros and cons of folding all
previous parallel physical topics into SPI-2.  Gene repeatedly brought
the group back to the question of whether SPI-2 requires SCAM.  He
noted that the SCA connector (the only internal connector described in
SPI-2) does not require SCAM.

Paul Aloisi produced the following list of SPI-2 contents:

     An Incremental Document to SCSI-3 SPI & Fast-20
     Defines new Speeds Fast-40 & Fast-80
     Defines LVD SCSI Interface
     Defines Universal Interface (SE/LVD)
     Defines Universal Terminator
     Defines Termpwr Distribution - 5 Volt & 3.3 Volt
     Defines HVD (EIA485) SCSI Termination

     Undecided Issues
     - Hot Plugging Case 4 doesn't work on LVD SCSI
     - Is SCAM required?

The issue was deferred to the plenary meeting (where it was decided to
return to the original proposal of SPI-2 replacing all previous

     4.5  Clarification of When Parity Is Valid (96-162r0) [Penokie]

George Penokie presented very simple change proposal to add the words,
"at the receiver" to a description of the parity signals in SPI.  In
the absence of any objections, the working group recommended that the
plenary adopt the document for inclusion in SPI-2.

5.   Protocol Topics

     5.1  Problem with Non-interlocked Busses (96-173r0) [Monia]

Charles presented a proposal that extends the actions of ACA to the
The group discussed the proposal, examined other options, and delved
into a wide range of issues involving serial busses.

Eventually, the group decided that a dedicated meeting would be
necessary to discuss all the serial bus issues.  This was followed
by a lengthy discussion of how to provide pre-meeting input to enhance
the efficiency of the meeting.  The group agreed to request meeting
time on Monday afternoon of the July X3T10 meeting week.

     5.2  SIP and Command Queuing (96-112r0) [McGrath]

Jim McGrath reviewed a previous proposal that provisions be made for
simplified queuing.

          5.2.1     SAM and Task Management (96-170r0) [Johansson]

Peter Johansson presented a specific list of changes needed in the
SCSI documents to define the simplified queuing described by Jim
McGrath (96-170r0).  The proposal was discussed at length.  Jim
McGrath asked for a straw poll to endorse the concepts enumerated in
the proposal.  The straw poll passed 17:1.

     5.3  SAM-2 Changes (96-169r0) [Monia]

Charles Monia presented a list of proposed SAM-2 changes from SAM and
new material to be included in SAM-2. Peter Johansson provided some
additional advice on changes to Charles.  Otherwise, there was minimal
comment on Charles' proposal.

The review of SAM-2 proposals was followed by a lengthy discussion of
how SAM fits into the larger SCSI conceptual framework.  Charles
started the discussion by noting that several people have expressed
concerns about the difficulty of reading SAM and the notion that
reading SAM is not necessary.

     5.4  Tape Support on FC-AL (Reflector Messages) [Hagerman]

Doug Hagerman requested that SCSI and Fibre Channel experts attend the
SSC Working Group meeting on Thursday at 10 am to discuss Fibre
Channel problems with support for tapes.

6.   Command Set Topics

     6.1  Resolution of the SCSI-3 Primary Commands (SPC) Forwarding
          Comments [Weber]

The group discussed the substantial editing already performed on the
SPC and the need for more SPC review and editing meetings.  Meetings
were scheduled for the Fridays of the May and July plenary weeks.

     6.2  Review of SCSI-3 Enclosure Services (SES) [Snively]

The discussion opened with a comparison of SES and SCC (SCSI-3
Controller Commands) features.  Larry Lamers was concerned that the
two command sets provide substantially overlapping features.  Bob
Snively and George Penokie were able to satisfy Larry that some
inconsequential overlap exists but that the overlap is not as large as
Larry had feared.  Larry asked that SES and SCC-2 clearly describe
where the two command sets do and do not overlap.

Rod DeKoning presented a request for extensions to support multiple
sub-enclosures.  Discussion of the sub-enclosures data formats
produced a lengthy debate on the subject of unique IDs.  The results
of the unique ID discussion was that no changes are needed in Rod's
proposal, however, some changes may be needed in the SPC.  The
specifics of the needed SPC changes involved making some currently
optional features mandatory, but the details were never clearly
specified during the discussion.

Doug Hagerman objected to the flat addressing scheme in Rod's
proposal.  He felt that the hierarchical LUN addressing scheme should
be used.  The group discussed the objection at length.  Bob agreed to
add strong recommendations favoring the hierarchical addressing over
the flat addressing scheme.  In addition, he agreed to add the flat
addressing scheme in an annex.

George Penokie presented a request for minor changes in the device
element status entry resulting from SSA needs.  After a brief
discussion, Bob accepted the proposed changes with minor revisions.

     6.3  Clarification of sleep mode (96-141r1) [Penokie]

George reviewed the details of his proposal for clarification of the
START STOP UNIT command in SBC.  He described the need for the
clarification as coming from the separation of START STOP UNIT (in
SBC) and the Power Management Mode Page (in SPC).

In the review of the changes, the group discovered possible problems
with the SIP mapping of the TARGET RESET task management function.
This produced a lengthy discussion about how the problem should be

After much discussion, George agreed to revise his proposal to include
changes in SAM-2 adding a reset function that affects all targets on
an interconnect and adding a new task management function for wake-up
|from sleep mode.  George noted that he will not propose adding a set
power level task management function to SAM-2.  The group had
discussed the set power level function, but George felt unqualified to
represent the discussion properly in a written proposal.

Bob reported on a meeting regarding ATAPI sleep.  He described a
request that the ATAPI sleep state table be imported into SCSI.  He
stated his plans to review the ATAPI state table in comparison to
equivalent SCSI information and bring the results to the working
group.  Pete McLean was asked to offer a judgment regarding the
compatibility of the two sleep models.  He felt that they are similar,
but the names have been changed to protect the innocent.

Larry and Pete agreed to work with George Penokie to determine how
best to incorporate the ATAPI table in SCSI.  Later, George presented
the revised ATA power management figure showing how SCSI and ATA are
very similar in their power management schemes.

     6.4  Programmable Capacity Revisited (96-171r0) [Houlder]

Gerry Houlder presented a proposal to correct the usage of the Mode
Page header to set the largest logical block address available on a
disk (96-171r0).  The previously defined usage of zero caused serious
problems for existing software.  Gerry described the changes to the
definition of the zero value behavior and the addition of FFFFFFFFh as
a mechanism for requesting the disk to reset to its largest available

In the absence of any objections, the working group recommended that
the plenary adopt the proposal for inclusion in SPC.

     6.5  SCSI-3 Block Commands (SBC) Review [Milligan]

Gene presented revision 4 of SBC.  Numerous details of SBC were
discussed and Gene received substantial advice regarding needed
changes.  Six commands, (such as SEEK and REZERO UNIT) were defined to
be obsolete.

     6.6  SCC-2 Discussion [Penokie]

John described a project proposal for SCC-2 to be voted on at the
upcoming plenary meeting.

     6.7  Security Erase [Schultz/Lohmeyer]

John reviewed the security erase proposal.  It was obvious that the
proposal had not been developed in a sufficiently formal manner.  John
and Ralph agreed to prepare a formal proposal (see 96-186r0).

     6.8  MMC-2 and/or Additional CD-ROM Command Set Project   

Gene Milligan reported that X3T13 will develop an informal reporting
mechanism for listing command sets that are developed by other
organizations.  He described the mechanism as being similar to the
vendor ID list maintained by X3T10.  He noted that the list will cover
as many command sets as become known to X3T13.

     6.9  Additional XOR bit [Milligan, Reflector]

Gene reported on a question about the XOR commands.  The question was
received from the SCSI Reflector.  The group discussed the question
briefly and Gerry Houlder was volunteered to write a proposal based on
the Reflector and Working Group discussion.

7.   Other Topics

     7.1  Greater than 8GB Technical Report [Penman]

Larry reported that the 8 GB Technical Report has been edited into the
correct format.  He believes that the Technical Report should be
processed for forwarding using a letter ballot.  The reformatted
Technical Report will be in the next mailing.

     7.2  High Availability SCSI Profile (96-151r1) [Hagerman]

Doug reminded the group that the plenary will be asked to forward a
project proposal for a high availability technical report.  He then
presented a review of the topics that he envisioned being covered in
the technical report. Doug received advice regarding several items in
his topics presentation.

     7.3  STA Liaison [McGrath]

The relationship between the technical committee the trade association
was discussed.  The need for bi-directional communications between the
two committees was discussed, with some specific examples of the
benefits.  Timing issues for the joint meeting were considered.

After some discussion, the group decided to hold a separate STA -
X3T10 Liaison meeting to begin at 5 pm on Wednesday of the meeting

     7.4  Normative References

John and George reported on problems with normative references lists
in SCC.  The group discussed the required actions to fix the normative
references in SCC.  General procedures for handling normative
references also were discussed.

8.   Meeting Schedule

John reviewed the proposed meeting week schedule for July 1996.  The
next meeting of X3T10 SCSI Working Group will be July 16-17, 1996, in
Colorado Springs, CO at the Red Lion Hotel (719-576-8900), hosted by
Symbios Logic.

9.   Adjournment

The meeting was adjourned at 5:30 p.m. on Wednesday May 8, 1996.

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