Java Grande in a Nutshell

1
Java Grandein a Nutshell

• Workshop on Java for High Performance Network
  Computing
• September 2-3 1998 Europar Southampton
• Geoffrey Fox
• Northeast Parallel Architectures Center
• Syracuse University
• 111 College Place
• Syracuse NY
• gcf_at_npac.syr.edu
• http//www.javagrande.org
• http//www.npac.syr.edu/users/gcf/jgeurosept98

2
Abstract of EuroTools Java Grande Presentation

• We describe Java Grande Forum -- motivation and
  current status
• motivation discusses Java as a language and where
  it is clearly good and where it could be good!
• This has numerical and distributed computing
  working groups and one project is a community
  activity to define
• Seamless interfaces allowing universal access to
  general hosts
• can be CORBA facility or Java framework

3
Why is Java Worth Looking at?

• The Java Language has several good design
  features
• secure, safe (wrt bugs), object-oriented,
  familiar (to C C and even Fortran programmers)
• Java has a very good set of libraries covering
  everything from commerce, multimedia, images to
  math functions (under development at
  http//math.nist.gov/javanumerics)
• Java has best available electronic and paper
  training and support resources
• Java is rapidly getting best integrated program
  development environments
• Java naturally integrated with network and
  universal machine supports powerful write
  once-run anywhere model
• There is a large and growing trained labor force
• Can we exploit this in computational science?

4
What is Java Grande?

• Use of Java for
• High Performance Network Computing
• Scientific and Engineering Computation
• (Distributed) Modeling and Simulation
• Parallel and Distributed Computing
• Data Intensive Computing
• Communication and Computing Intensive Commercial
  and Academic Applications
• HPCC Computational Grids ..
• Very difficult to find a conventional name that
  doesnt get misunderstood by some community!

5
What is the Competition?

• So existing Grande codes are written in Fortran C
  and C with a clearly unattractive and
  comparatively unproductive programming
  environment
• These current languages and tools are sufficient
  but does not seem likely that can build much
  better environments around them
• Fortran77 has excellent compilers, good user base
  but will not be taught broadly and clearly
  limited in capabilities in particular not object
  oriented
• Fortran90 and HPF will not make it (reasons not
  important)
• Subsume discussion of C under that of C
• Five years ago, it looked as though C could
  become language of choice (perhaps with Fortran
  as inner core) but this appears stalled
• The language is complex and splintered with no
  agreement on Grande standards -- partly because
  use in Grande applications is too small to
  motivate standards and partly due to culture
• Java halted Cbandwagon
• So there is no competition -- Java is currently
  our only hope

6
Why could Java succeed where Fortran and C
failed?

• It has some natural advantages due its internet
  base with threads and distributed computing
  built in
• It is a young language and we can take steps now
  to avoid unproductive proliferation of libraries
  and parallel constructs
• We could be third (Fortran, C, Java) time lucky
• It could have expressivity and object oriented
  advantages of C combined with performance
  levels of C and Fortran
• It can use its clear GUI advantages as an entrée
  into other aspects of Grande programming

7
Synergy of Parallel Computing and WebInternetics
as Unifying Principle

• The two forms of Large Scale ComputingScale
  Computer for Scale
  Users in ProportionPower User
  to number of computers
• Parallel
  Commodity Distributed Computers
  Information Systems Technologylt-------
  -------- Internetics Technologies
  ---------------gt

1market
99 of market driving student interest and (Java)
technologies
Parallel Computer
Distributed Computer HPF MPI
Java HTML
XML
8
The 3 Roles of Java
9
Java and multi-tier Grande Systems
Java wins today?
Java Grande should promote
Parallel or Sequential Java Grande Codes
Java Applet Clients
Java Servers
Geographically Distributed Grandecomputer
Resources
Gateway System hosting Seamless Access Database,
Collaboration Visualization and other Services
GeographicallyDistributed users
10
What is Goal of Java Grande Forum?

• Java has potential to be a better environment for
  Grande application development than any
  previous languages such as Fortran and C
• The Forum Goal is to develop community consensus
  and recommendations for either changes to Java or
  establishment of standards (frameworks) for
  Grande libraries and services
• These Language changes or frameworks are designed
  to realize best ever Grande programming
  environment
• First Meeting Mar 1 Palo Alto at Java 98 -- 200
  Attendees set Agenda -- 30 permanent people and
  further meetings May 9-10, Aug 6-7
• Public Discussion SC98 Orlando November 13 (3
  hour panel)
• http//www.npac.syr.edu/projects/javaforcse
• http//www.javagrande.org

11
Two types of Things we are doing

• 1) Most important in the near term -- encourage
  Sun to make a few key changes in Java to allow it
  to be a complete efficient Grande Programming
  Language
• floating point, arrays, complex etc.
• 2) As a community, recognize that sometimes
  standards are more appropriate than creativity
  and pool results of experiments to produce a Java
  Grande framework covering libraries and computer
  access
• Fiscally important fields such as databases, have
  established such standards -- we should follow
  their example
• 1) requires us to work with the computing
  mainstream -- 2) is internal to community

12
Activities of the Java Grande Forum I

• Two major working groups promoting standards and
  community actions
• Numerics Java as a language for mathematics led
  by Ron Boisvert and Roldan Pozo from NIST
• Changes in Java controversial handling of
  floating point which currently has goal of
  reproducible results but this leads to non
  optimal accuracy
• Addition of Complex types or classes
• Lightweight classes and Operator overloading --
  enables implementation of complex as a class
• Fortran rectangular multidimensional arrays --
  Java naturally has arrays of arrays
• High quality math libraries with agreed
  interfaces -- FFT, Matrices, Transcendental
  functions

13
Gosling onOperator Overloading
Java Grande 98Feb 28 98
14
Activities of the Java Grande Forum II

• Distributed and Parallel Computing led by Dennis
  Gannon and Denis Caromel (INRIA, France)
• Performance of RMI (Attractive Java distributed
  object model - remote method invocation)
• Performance of Java runtime (the virtual machine
  VM) with lots of threads, I/O, memory use
• Parallel Computing interfaces including Java MPI
  binding
• Development of universal (Condor, Globus, Legion
  UNICORE WebSubmit ..) Java interface to computing
  resources -- enables seamless computing (easier
  than metacomputing!)
• Special seamless computing meeting at Argonne
  October 98
• Development of Grande Application benchmarks
• http//math.nist.gov/scimark

15
Where are we now?

• Both working groups have made substantial
  progress
• Numerics working group has proposals essentially
  ready for Sun
• Concurrency working group will propose modest RMI
  changes
• We are initiating Community actions
• Help us collect Java Grande benchmarks
• Work with community on standard classes and
  libraries
• Participate in seamless computing framework
• Stress Java and Java runtime (the VM) with large
  applications -- where are performance problems?
• Join us at SC98 November 13
• Note European involvement has been excellent so
  far
• Caromel, Getov, Phillipsen
• Edinburgh and NAG

16
Java Seamless Computing Framework orCORBA
Facility for Computation

• Allows Universal Access to all computers from the
  same Java Applet Front EndInfrastructure for
  Metacomputing, Performance Modeling, Interfacing
  computers and data to distributed computational
  objects

17
What/Why is a Framework?

• Java Calls (mainly Interfaces and not methods) to
  capabilities expressed in implementation neutral
  form
• Drivers convert these general calls to vendor
  specific implementation of service
• Java code can either be all on client (2-tier) or
  on client and middle tier (3 tier)
• e.g. JDBC (Java Database Connectivity) is a
  universal interface to all relational databases
• Adoption of this JDBC implies that vendor
  specific solutions are immediately less
  attractive
• All vendors must however support JDBC because of
  importance of seamless interfaces!

18
JDBC Database Framework Architecture
Java applications
JDBC API
JDBC API
JDBC Driver API
JDBC Driver manager
19
Proposed Java Computing Services Framework I

• Enables development of Web Interfaces to run a
  given job on any computer with any data source
  compliant with this framework just as JDBC gives
  a universal interface to any relational database
• i.e. enables seamless computing which is a part
  of metacomputing but not as ambitious
• Metacomputing in addition allows linkage of
  multiple computers to run together on a single
  job
• The Computing Services Framework will allow
  vendors to compete on either User Front End (GUI)
  or back end services with the JavaCS framework
  providing universal linkage
• The framework is implemented at the backend as a
  set of drivers which map generic Java Interfaces
  to particular software (e.g. a compiler) on
  particular machines.
• System vendors would be asked to deliver support
  for JavaCS as part of RFP

20
Proposed Java Computing Services Framework II

• Requires agreement by suitable interested
  parties on
• what are the services
• what are the interfaces for a given service
• As with JDBC and Oracles PL/SQL can lead to
  difficult choices!
• Old (seamless workshop Reading Sept 97) link is
  http//www.sis.port.ac.uk/mab/Computing-FrameWork
  /
• Abstract ideas developed in Condor Globus Legion
  and PACE POEMS PetaSIM for harder problems
  (metacomputing / performance specification) and
  developed for seamless problem by Sweb (Cornell)
  WebSubmit (NIST) or UNICORE (Europe)
• Who else should we would be talking to?

21
Possible Services in a Java Computing Framework -
I

• Grande Resource Discovery, Allocation and
  Scheduling
• Recent JINI Sun technology looks attractive
• We are defining methods and properties of
  computers and programs viewed as distributed
  objects
• Thus we are inevitability defining a CORBA
  facility for computing
• Compiling, Executing, Specification of features
  needed for execution optimization
• This includes parameters needed by MPI/HPF
  decompositions such as number of processors
• Resource Management and Scheduling jobs as in
  Codine or LSF or commercial NT environments
• Accounting -- integrate with Web commerce
  technology?
• Authentication, Security (especially hard in
  metacomputing as link several different
  management policies)
• Public Key Infrastructure expected from Internet
  commerce very important

22
Possible Services in a Java Computing Framework -
II

• Sharing, Accessing and Storing into File Systems
• Data and Performance Visualization Interface (how
  applets access server side information)
• Performance measurement and recording (cf Pablo
  SDDF)
• Interfaces for Programming Tools
• Debuggers
• Computational Steering / Interpreted Execution
• Libraries including names in generalized Math
  class and
• Java Grande defining this in numerics working
  group
• Module linkage model for metaproblems
  (multidisciplinary applications) could be
  outside scope -- can we use standard JavaBean
  approach?

23
What should you do as a Java Grande believer?

• Dont need to rewrite existing codes in Java!
• Rather use Java freely at client and gateway
  tier
• Wrap existing codes as CORBA or Java distributed
  objects
• Conduct suitable experiments in using Java in
  complete Grande applications
• Make certain your interests are represented in
  Java Grande Forum
• Retrain your staff in Java Web and distributed
  object technologies
• Put High Performance Grande Forum compliant
  Java support into your RFPs for hardware and
  software

24
Multi Tier Gateway Architecture
Clients
Gateway Systems as Middle Tier
High Performance Computing and Communication Tier
25
Multi-Server Gateway Tier
MultidisciplinaryControl (WebFlow)
Gateway Control
Parallel DBProxy
Database
NEOS ControlOptimization
OptimizationService
Origin 2000Proxy
MPP
NetSolveLinear Alg.Server
Matrix Solver
Agent-basedChoice ofCompute Engine
IBM SP2Proxy
Data AnalysisServer
MPP