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CSharp · Console

/Program.cs

using System;
using System.Threading;
using System.Threading.Tasks;
using System.Linq;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Diagnostics;

public class Program
{
    public static void Main()
    {
        Console.WriteLine($"FrameworkDescription: {RuntimeInformation.FrameworkDescription}");
        Console.WriteLine($"OSVersion: {Environment.OSVersion}");
        Console.WriteLine($"Environment.ProcessorCount: {Environment.ProcessorCount}");
        ThreadPool.SetMinThreads(workerThreads: 100, completionPortThreads: 10);
        HashSet<Thread> threads = new();
        int concurrency = 0;
        int maxConcurrency = 0;
        Parallel.ForEach(Enumerable.Range(1, 1500), n =>
        {
            lock (threads) maxConcurrency = Math.Max(maxConcurrency, ++concurrency);
            lock (threads) threads.Add(Thread.CurrentThread);
            // Simulate a CPU-bound operation that takes 200 msec
            Stopwatch stopwatch = Stopwatch.StartNew();
            while (stopwatch.ElapsedMilliseconds < 200) { }
            lock (threads) --concurrency;
        });
        Console.WriteLine($"Number of unique threads: {threads.Count}");
        Console.WriteLine($"Maximum concurrency: {maxConcurrency}");
    }
}