How do I compile and run this parallel program?
Michael
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import Control.Parallel
nfib :: Int -> Intnfib n | n <= 1 = 1 | otherwise = par n1 (seq n2 (n1 + n2 + 1)) where n1 = nfib (n-1) n2 = nfib (n-2)
{-nfib :: Int -> Intnfib n | n <= 1 = 1 | otherwise = nfib (n-1) + nfib (n-2)-}
main = do putStrLn $ show $ nfib 39
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[michael@hostname ~]$ ghc --make -threaded nfib.hs[michael@hostname ~]$ ./nfib +RTS -N3nfib: the flag -N3 requires the program to be built with -threadednfib: nfib: Usage: <prog> <args> [+RTS <rtsopts> | -RTS <args>] ... --RTS <args>nfib: nfib: +RTS Indicates run time system options follownfib: -RTS Indicates program arguments follownfib: --RTS Indicates that ALL subsequent arguments will be given to thenfib: program (including any of these RTS flags)nfib: nfib: The following run time system options are available:nfib: nfib: -? Prints this message and exits; the program is not executednfib: --info Print information about the RTS used by this programnfib: nfib: -K<size> Sets the maximum stack size (default 8M) Egs: -K32k -K512knfib: -k<size> Sets the initial thread stack size (default 1k) Egs: -k4k -k2mnfib: nfib: -A<size> Sets the minimum allocation area size (default
512k) Egs: -A1m -A10knfib: -M<size> Sets the maximum heap size (default unlimited) Egs: -M256k -M1Gnfib: -H<size> Sets the minimum heap size (default 0M) Egs: -H24m -H1Gnfib: -m<n> Minimum % of heap which must be available (default 3%)nfib: -G<n> Number of generations (default: 2)nfib: -T<n> Number of steps in younger generations (default: 2)nfib: -c<n> Use in-place compaction instead of copying in the oldest generationnfib: when live data is at least <n>% of the maximum heap size set withnfib: -M (default: 30%)nfib: -c Use in-place compaction for all oldest generation collectionsnfib: (the default is to use copying)nfib: -w Use mark-region for the oldest generation (experimental)nfib: nfib: -t[<file>] One-line GC statistics (if <file> omitted, uses stderr)nfib: -s[<file>] Summary GC statistics (if <file> omitted, uses
stderr)nfib: -S[<file>] Detailed GC statistics (if <file> omitted, uses stderr)nfib: nfib: nfib: -Z Don't squeeze out update frames on stack overflownfib: -B Sound the bell at the start of each garbage collectionnfib: nfib: -hT Heap residency profile (output file <program>.hp)nfib: -i<sec> Time between heap samples (seconds, default: 0.1)nfib: nfib: -C<secs> Context-switch interval in seconds.nfib: 0 or no argument means switch as often as possible.nfib: Default: 0.02 sec; resolution is set by -V below.nfib: -V<secs> Master tick interval in seconds (0 == disable timer).nfib: This sets the resolution for -C and the profile timer -i.nfib: Default: 0.02 sec.nfib: nfib: --install-signal-handlers=