habr 803273 example

Program.cs

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using Threading;

public static class Program
{
    static void Main(string[] args)
    {
        var summary = BenchmarkRunner.Run<Bench>();
    }

    [ThreadingDiagnoser]
    public class Bench
    {
        [Params(10, 100, 1000, 10_000)]
        public int Repeat;

        [Benchmark]
        public void Lock()
        {
            var a = new Lock();
            for (int i = 0; i < Repeat; i++)
            {
                a.SomeMethod();
            }
            a.Assert(Repeat);
        }

        [Benchmark]
        public void QueueExample()
        {
            var a = new SerialQueueExample();
            for (int i = 0; i < Repeat; i++)
            {
                a.SomeMethod();
            }
            a.Assert(Repeat);
        }

    }

    class Lock
    {
        readonly object locker = new object();
        private int counter = 0;

        public void SomeMethod()
        {
            lock (locker)
            {
                counter++;
            }
        }

        public void Assert(int input)
        {
            if (input != counter)
            {
                throw new InvalidOperationException($"Input {input}, counter {counter}");
            }
        }
    }

    class SerialQueueExample
    {
        readonly SerialQueue queue = new SerialQueue();
        private int counter = 0;

        public void SomeMethod()
        {
            queue.DispatchAsync(() => {
                counter++;
            });
        }

        public void Assert(int input)
        {
            if (input != counter)
            {
                throw new InvalidOperationException($"Input {input}, counter {counter}");
            }
        }
    }
}

Выше ошибка, вместо DispatchAsync нужно использовать DispatchSync
Тогда производительность на линейном чтении отвратительная:

Method	Repeat	Mean	Error	StdDev	Median	Completed Work Items	Lock Contentions
Lock	10	172.3 ns	1.65 ns	1.55 ns	171.8 ns	-	-
QueueExample	10	70,694.3 ns	3,443.19 ns	10,152.32 ns	68,911.5 ns	9.9977	-
Lock	100	1,653.5 ns	27.56 ns	25.78 ns	1,650.7 ns	-	-
QueueExample	100	630,806.0 ns	18,771.76 ns	55,348.95 ns	627,627.9 ns	99.9912	-
Lock	1000	16,217.1 ns	129.39 ns	121.03 ns	16,173.7 ns	-	-
QueueExample	1000	6,623,032.2 ns	217,067.14 ns	640,027.37 ns	6,619,225.0 ns	999.8203	-
Lock	10000	160,593.7 ns	671.25 ns	595.05 ns	160,679.1 ns	-	-
QueueExample	10000	62,459,690.0 ns	2,151,567.18 ns	6,242,086.51 ns	59,985,133.3 ns	9997.6667	-