using System;

using System.Diagnostics;

using System.Threading;

using System.Threading.Tasks;

using Polly;

using Polly.Timeout;

​

public class Program

{   

    public static async Task Main()

    {

        var timeout = TimeSpan.FromMilliseconds(50); 

        var pessimisticTimeoutPolicy = Policy.TimeoutAsync(

            timeout, 

            TimeoutStrategy.Pessimistic, 

            onTimeoutAsync: (ctx, ts, task) => task.ContinueWith( t => _ = t));

        var timer = Stopwatch.StartNew();

        try 

        {

            await pessimisticTimeoutPolicy.ExecuteAsync(async ct => await DoSomethingAsync(ct), CancellationToken.None);

            Console.WriteLine($"Timer : {timer.ElapsedMilliseconds} ms");

        }

        catch (TimeoutRejectedException e)

        {

            Console.WriteLine($"Timer : {timer.ElapsedMilliseconds} ms");

            Console.WriteLine(e.Message);

        }

    }

    private static async Task DoSomethingAsync(CancellationToken ct)

    {

        await Task.Delay(100, ct);

    }

}