Scripted HTML version of Foils prepared 12 November 1996

Foil 8 Pipeline Algorithm in detail

From CPS615-End of N-Body Discussion and Beginning of Numerical Integration Delivered Lectures of CPS615 Basic Simulation Track for Computational Science -- 15 October 96. by Geoffrey C. Fox *
Secs 198.7
Case when i compared to i is not needed as particles dont interact with themselves
At step k, interact particle i with particle j= 1 + mod((i+k-1),N)
Accumulate force on i due to j in fixed Ai
Accumulate negative of this as force on j due to i in circulating Acj
At the end of the algorithm, add Ai and Aci
In parallel version, Note that Ai will be calculated in "home processor for particle i but Aci will travel around the machine being accumulated in processor holding particle j
Thus this violates the owner computes rule and so this parallel algorithm must be implemented by hand -- the compiler will not find it automatically



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