[Performance] on calcPmt()

[yellowbean]

Profile

stack exec --profile -- Hastructure-exe +RTS -p
~/.cabal/bin/profiteur Hastructure-exe.prof

Hastructure-exe.prof.html.zip

Stack Frame

Result

The function "calcPmt" takes 95% of time in a pool run ( 300 mortgages), roughly 20 seconds in LOCAL

Problem

How to optimize the function at

Hastructure/src/AssetClass/AssetBase.hs

Line 55 in e180f20

calcPmt bal 0.0 periods = divideBI bal periods

?

the logic seems simple and little room to improve ,is it the scenario that user shall replace this function with C DLL to boost performance ?( if it will boost )

The code pilot suggest, but it yields nothing, probably GHC has already optimized.

calcPmt bal periodRate periods =
    let
      periodRate1 = toRational periodRate
      r1 = (1 + periodRate1) ^ periods
      pmtFactor = periodRate1 * r1 / (r1 - 1)
    in
      mulBR bal pmtFactor