December 14-16, 1998

LBL, Berkeley, CA

December 14, 1998

The meeting began at 9:30am. List of 10 eligible voters: NAG, UT, UC Berkeley, Bell Labs, HP/Convex, Tera, NIST, Univ of Notre Dame, Sandia, Univ of Houston.

A tentative agenda for the meeting shall be:

It was also stressed that we need volunteers for reference implementations and test codes. Subgroups met to discuss individual chapters.

At 11am, the naming convention issue was addressed. We need to decide on cblas_ prefix. Different name for the new stuff, or change the name in the appendix? A straw vote was taken.

  1. Proposal is for F95, gemm( -- ) module f95_blas
    F77, F_DGEMM( -- )
    C, c_dgemm( -- )
    c legacy, cblas_dgemm( -- )
    Straw vote 9 in favor,
  2. Proposal for f95 f95blas_
    F77 F77BLAS_
    C cblas_
    clegacy ?
    Straw vote 2 in favor,
  3. Proposal for f95 blas_
    f77 FBLAS_
    C legacy
    Straw vote 0 in favor
  4. Proposal for f95blasv2_
    Straw vote 2 in favor

We then began a second reading of Chapter 1. Specific "wording" revisions were suggested for each section, and those revisions have been incorporated into the chapter. We need to add bibliographical references for F77 and C standards to this chapter. Formal votes were taken on:

Chapter 2 was then addressed. Should we have band and packed MM routines? But for performance, we need different storage. A straw vote was taken on having this functionality-- 13/0/1. Specific "wording" revisions were suggested for each section, and those revisions have been incorporated into the chapter. Formal votes were taken on:

At 3:30pm, we began discussion of the Extended Precision chapter. Jim gave an overview of the chapter, and then Dave Bailey discussed the implementation of extended precision BLAS.

At 4:30pm, Sven addressed the F95 choice of interface decision. Optional arguments or key arguments. Decision delayed until the next day.

The meeting adjourned at 5pm.

December 15, 1998

The meeting began at 9am. Discussion continued on Chapter 2. We need to document the abs value of complex numbers. We debated the readdition of matrix copy. Combine functionality of slasr and slartv.

At 1:15pm, we began discussion on the Sparse BLAS chapter.

We took a vote to remove the unnecessary "const" from in front of certain parameters. Vote was 8/0/2. This affects Chapters 2 and 3, and the Legacy BLAS chapter.

We took a straw vote on the framework of Sparse BLAS chapter. Vote was 10/0/2.

We then readdressed the key-args versus optional args issue. A straw vote was taken was take on those in favor of key arguments interface -- 6/2/6. A formal vote was taken on those in favor of OPTIONAL arguments with derived types for operator arguments -- 8/1/1.

At 4pm, we had a conference call with Ken Stanley to discuss the inclusion of GEMVT and TRMVT interfaces in Chapter 2 (section 2.2.5). It was decided that TRMVT was mature enough and should be included, whereas the interface for GEMVT was still under discussion.

The meeting adjourned at 5pm.

December 16, 1998

The meeting began at 8:30am with the discussion of the Interval BLAS chapter. Chenyi began by reviewing the changes that were made since the last meeting. It was decided that the motivational section should be moved to the end of the chapter as an appendix, and should be expanded to include more information on why it is important and include an example. Restructuring of sections to resemble other chapters.

Jim Demmel then led the discussion on the voting of the chapter. Discussion began on the discussion of machine constants in the chapter. The definition of overflow is not defined, and delegated to another committee. Some of the issues seemed more compiler-related rather than BLAST committee related.

The definition of an empty interval (Section 5.2.3, Special Intervals) needs a more concrete specification. Section 5.2.3, the implementation of an empty interval is language dependent. Formal vote on allowing the definition of an empty interval to be language dependent, 9/0/0.

Naming conventions, suffix _i to be added at the end of the name, e.g., f_sgemm_i. Formal vote, 8/0/0. Remove discussion of extended precision routines in this chapter. Major revisions necessary in Section 5.4 and 5.5.

The forum then began general discussion. It was agreed to have another on-line meeting at the end of January. The final meeting will be on March 16--18, 1999 in Knoxville, Tennessee.

Jim Demmel then discussed test software for the extended precision chapter and the need for an environmental inquiry function. However, the parameters needed in this environmental inquiry routine for the extended precision routines are more complex than for the routines in the other chapters. So it was decided to have two separate inquiry routines instead of making one general routine. This would avoid the unnecessary complication for the other chapters.

It was also stated that Strassen's algorithm is allowed in Chapter 2 (Dense and Banded BLAS) but not in Chapter 4 (Extended and Mixed Precision BLAS).

Jim Demmel and Susan Blackford then discussed specific revisions to Chapter 2 over lunch. One specific revision suggested was to divide Table 2.1 (Reduction Operations) into two tables, one for reduction operations and one for rotation operations. And for the "dot product" routines (DOT, DOTU, DOTC), only one routine is needed. An additional CONJ parameter will be added to accomodate the complex conjugate version of the routine. The same logic will be applied to GER, GERU, GERC.

The meeting adjourned at 12:30pm.

Attendees list for the December 14-16, 1998 BLAST Forum Meeting

David Bailey         LBL, NERSC 
Puri Bangalore       MSU-ERC    
Susan Blackford      UT, Knoxville
Jim Demmel           UC Berkeley
Jack Dongarra        UT / ORNL  
Sven Hammarling      NAG, UK    
Mike Heroux          Sandia Nat Lab
Mary Beth Hribar     Tera Computer
Chenyi Hu            UH-DT      
Rich Lee             UND        
Sherry Li            LBL, NERSC 
Hsin-Ying Lin        HP Convex Tech. Ctr.
Andrew Lumsdaine     UND        
Linda Kaufman        Bell Labs  
Roldan Pozo          NIST       
Jeremy Siek          UND        
Clint Whaley         UT, Knoxville

Susan Blackford agreed to take minutes for the meeting.