map benchmark

map.fs

open System.Collections.Concurrent
open System.Threading.Tasks
open BenchmarkDotNet.Attributes
open BenchmarkDotNet.Configs
open BenchmarkDotNet.Running
open BenchmarkDotNet.Jobs
open System

// Learn more about F# at http://fsharp.org
// See the 'F# Tutorial' project for more help.

let mapNew (f: 'T -> 'U) (array : 'T[]) : 'U[]=                
                let inputLength = array.Length
                let result = Array.zeroCreate inputLength                
                let rangePartition = Partitioner.Create(0,inputLength)                   
                Parallel.ForEach(rangePartition, 
                    fun (start,finish) _  ->
                        for i in start .. finish - 1 do
                            result.[i] <- f array.[i]) |> ignore
                result

let mapOld (f: 'T -> 'U) (array : 'T[]) : 'U[]=                
                let inputLength = array.Length
                let result = Array.zeroCreate inputLength
                Parallel.For(0, inputLength, fun i ->
                    result.[i] <- f array.[i]) |> ignore
                result

[<MemoryDiagnoser>]
type ParallelBench () =
    let mutable array = [||]
    let mutable intArray = [||]

    [<Params (1000,10000,50000,100000,1000000)>]
    member val public Length = 0 with get,set

    [<Setup>]
    member self.SetupData() =
        array <- Array.create self.Length 2.0
        intArray <- Array.create self.Length 2

    [<Benchmark>]
    member self.MapOldDistanceFloats() =
        array |> mapOld (fun x -> System.Math.Sqrt(x*x+x*x))

    [<Benchmark>]
    member self.MapNewDistanceFloats() =
        array |> mapNew (fun x -> System.Math.Sqrt(x*x+x*x))

    [<Benchmark>]
    member self.MapOldPlus1Ints() =
        intArray |> mapOld (fun x -> x+1)

    [<Benchmark>]
    member self.MapNewPlus1Ints() =
        intArray |> mapNew (fun x -> x+1)

[<EntryPoint>]
let main argv = 
    BenchmarkRunner.Run<ParallelBench>(ManualConfig.Create(DefaultConfig.Instance).With(Job.RyuJitX64)) |> ignore
    0 // return an integer exit code