Small benchmark of differenet immutable sets perfomance

contactsSetBench.fs

open BenchmarkDotNet.Attributes
open BenchmarkDotNet.Running
open System
open System.Security.Cryptography
open System.Collections.Immutable
open Bogus

type Contact =
    { Id: string
      Phone: string
      FirstName: string
      LastName: string }
      
let genContacts (num:int) =
    Bogus
        .Faker<Contact>()
        .CustomInstantiator(fun f ->
            {
            Id = f.UniqueIndex.ToString()
            Phone = f.Phone.PhoneNumber()
            FirstName = f.Person.FirstName
            LastName = f.Person.LastName
            })
        .Generate(num)

let _contacts = genContacts(100000)

let contacts1, contacts2  = (_contacts.GetRange(0,75000),_contacts.GetRange(45000,55000))
printfn "Gathered %i contacts1, %i contacts2" contacts1.Count contacts2.Count

type ContactsBench() =
    [<Benchmark>]
    member _.FSSet()=
        let intersection = Set.intersect (Set.ofSeq contacts1) (Set.ofSeq contacts2)
        printfn "There were %i intersections for F# Set" intersection.Count
    
    [<Benchmark>]
    member _.IHSet() =
        let c1 = ImmutableHashSet.CreateRange(contacts1)
        let c2 = ImmutableHashSet.CreateRange(contacts2)
        let intersection = c1.Intersect(c2)
        printfn "There were %i intersections for ImmutableHashSet" intersection.Count

    [<Benchmark>]
    member _.ISSet() =
        let c1 = ImmutableSortedSet.CreateRange(contacts1)
        let c2 = ImmutableSortedSet.CreateRange(contacts2)
        let intersection = c1.Intersect(c2)
        printfn "There were %i intersections for ImmutableSortedSet" intersection.Count


[<EntryPoint>]
let main argv =
    let sets = BenchmarkRunner.Run<ContactsBench>()
    0

Summary.md

BenchmarkDotNet=v0.12.1, OS=macOS Catalina 10.15.4 (19E287) [Darwin 19.4.0] Intel Core i9-9980HK CPU 2.40GHz, 1 CPU, 16 logical and 8 physical cores .NET Core SDK=3.1.301 [Host] : .NET Core 3.1.5 (CoreCLR 4.700.20.26901, CoreFX 4.700.20.27001), X64 RyuJIT DEBUG DefaultJob : .NET Core 3.1.5 (CoreCLR 4.700.20.26901, CoreFX 4.700.20.27001), X64 RyuJIT

Method	Mean	Error	StdDev
FSSet	331.9 ms	5.82 ms	9.73 ms
IHSet	159.1 ms	2.98 ms	4.98 ms
ISSet	107.4 ms	2.07 ms	2.76 ms