Records vs Interfaces speed

bench.fs

namespace Benchmarks

open BenchmarkDotNet.Attributes
open System.IO
open System.Runtime.CompilerServices


[<Interface>]
type ILogger =
     abstract Info: string -> unit

type LogClass() =
    member this.Info0 (i: string) =
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)

    interface ILogger with
        member this.Info i =
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)

module LogRec2 =
    let log2 (i: string) =
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)
        TextWriter.Null.WriteLine(i)

type LogRec =
    {
        Info: string -> unit
    }

//[<MemoryDiagnoser>]
type RecordVsLambda() =
    
    let text = "abcd"
    let classExample = LogClass()
    let interfaceExample = LogClass() :> ILogger
    let recordExample = 
        { Info = fun i ->
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)
            TextWriter.Null.WriteLine(i)        }

    let recordExample2 = 
        { Info = LogRec2.log2  }
    
    [<Benchmark(Baseline=true)>]
    member _.InterfaceExample() = 
        interfaceExample.Info text
        interfaceExample.Info text
        interfaceExample.Info text

    [<Benchmark>]
    member _.RecordExample() = 
        recordExample.Info text
        recordExample.Info text
        recordExample.Info text

    [<Benchmark>]
    member _.RecordExample2() = 
        recordExample2.Info text
        recordExample2.Info text
        recordExample2.Info text

    [<Benchmark>]
    member _.ClassExample() = 
        classExample.Info0 text
        classExample.Info0 text
        classExample.Info0 text

    [<Benchmark>]
    member _.ByHand() = 
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)
        TextWriter.Null.WriteLine(text)

results.txt

BenchmarkDotNet=v0.12.0, OS=Windows 10.0.18363
AMD Ryzen 7 2700X, 1 CPU, 16 logical and 8 physical cores
.NET Core SDK=3.1.101
  [Host]     : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT DEBUG
  DefaultJob : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT


|           Method |      Mean |     Error |    StdDev | Ratio | RatioSD |
|----------------- |----------:|----------:|----------:|------:|--------:|
| InterfaceExample | 6.6501 ns | 0.0731 ns | 0.0648 ns |  1.00 |    0.00 |
|    RecordExample | 3.5110 ns | 0.0595 ns | 0.0556 ns |  0.53 |    0.01 |
|   RecordExample2 | 8.3540 ns | 0.1371 ns | 0.1283 ns |  1.25 |    0.02 |
|     ClassExample | 5.6655 ns | 0.0624 ns | 0.0584 ns |  0.85 |    0.01 |
|           ByHand | 0.7271 ns | 0.0115 ns | 0.0107 ns |  0.11 |    0.00 |