1. Architecture of Scalable Libraries
   1. Michael Hearn Illinois
2. Hearn Presentation -- Questions
   1. *Usability -- Must Hide Complexity
   2. *Software Development costs time ...
      1. -Immature Computing Environment
      2. -Moving Targets
      3. -Lack of standards
      4. -Complexity
   3. *Portability
      1. -No standard or dominant parallel architecture
      2. -Programming Investment not protected
3. Hearn -- Answers to problems
   1. -more BLAS?
   2. -Object Oriented?
   3. -PSE's ?
4. Grimes -- Background
   1. *Manages Mathematical software group in Boeing
   2. *Hired by Sinjovec while he was at Boeing
   3. *BCSLIB is Boeing's IMSL
   4. *Supports sparse matrix library at Boeing
5. Grimes -- Why is Library/PSE succesful
   1. *Solves a problem that somebody wants
   2. *Useful Interfaces
   3. *Transportable -- must run on 10 platforms from mainframe to many types of WS/PC's
   4. *Affordable sustaining costs
   5. *Can be extended/modified easily
   6. *efficient
   7. *solves as big a problem as possible
6. Sinjovec
   1. *Scalable libraries are building blocks
   2. *Multimedia Interface
   3. *Geographically distributed
   4. *Likes WWW and suggests need software tools to exploit
   5. *Paradigm shift from homogeneous MPP to metacomputing
   6. *PSE is everything available on network
7. Sinjovec
8. Object-Oriented Approach
   1. *Abstract Data types(ADT)
      1. -ADA Modula2 find programs easier to write/re-use
   2. *Interfaces are independent of implementation whereas
      1. -subroutine libraries require user to understand data structures and algorithms
   3. *Parallel Programming
      1. -encapsulate parallelism in coarse grain objects
9. Sinjovec Briefing I
   1. *Has example of ADA to Fortran linking where needed to use packages to hide Fortran data structures
   2. *Standards for parallel objects are needed
      1. -HPF has started this
   3. *Tools that enhance re-use such as CORBA/OLE are needded but these are sequential
10. Sinjovec Briefing II
    1. *Interested in secure repositories -- don't keep bringing software over net
       1. -compute servers
    2. *Is an ADA fan
    3. *Has a set of language object oriented features
    4. *need heirarchy of object-oriented abstractions -- ADT's
11. Skjellum Briefing
    1. *Skjellum agrees with Sinjovec
       1. -Software engineering should be studied and used
    2. *Standard components are not used now!
    3. *Inheritance is a limited value
    4. *hierarchies produce inefficiences as a lot of copying
12. Questions from the Audience--I
    1. *Hearn -- can one achieve these wonderful software engineering goals?
    2. *Abstraction can lead to higher performance (as allows optimal implementation) or lower performance if too much copying
    3. *Must make libraries allow any decomposition
    4. *Can one cope with changing decompositions between library components
    5. *Don't answer question if realistic to implement!
13. Questions from the Audience - II
    1. *PBLAS attacked as incomplete by Johnsson and Skjellum
       1. -Need multiple simultaneous problems
       2. -separate operations and data/data layout
    2. *Smith has an approach that seems inconsistent with HPF and does not accept people with a different approach.
    3. *Grimes and Smith use C plus MPI as only transportable solution
14. Questions from the Audience -III
    1. *Skjellum does not believe in HPF - says C++ will dominate
    2. *Demmel is concerned about portability of numbers between different platforms
       1. -algorithms need to be robust in this area!
       2. -Hearn notes that no two computers agree on the time
    3. *Rice notes no correctness proof is realistic in any real problem