HTML version of Scripted Foils prepared 29 December 1996

Foil 10 What gives high performance in HPF

From CPS615-Introduction to Virtual Programming Lab -- Problem Architecture Continued and Start of Real HPF Delivered Lectures of CPS615 Basic Simulation Track for Computational Science -- 26 September 96. by Geoffrey C. Fox *
Secs 318.2
1 There is tradeoff between parallelism and communication
2 Programmer defines the data mapping and compiler uses this to assign processing
3 Underlying assumptions are that:
4 An operation on two or more data object is likely to be carried out much faster if they all reside in the same processor,
5 And that it may be possible to carry out many such operations concurrently if they can be performed on different processors
6 This is embodied in "owner computes" rule -- namely that in for instance
  • A(i,j)= .....
  • One brings everything on right hand side to process "owning" A(i,j) and performs computation in this processor
7 Owner computes algorithm is usually good and often best

Table Font Size


© Northeast Parallel Architectures Center, Syracuse University, npac@npac.syr.edu

If you have any comments about this server, send e-mail to webmaster@npac.syr.edu.

Page produced by wwwfoil on Fri Aug 15 1997