Why are try blocks expensive?

Question

I\'ve heard the advice that you should avoid try catch blocks if possible since they\'re expensive.

My question is specifically about the .NET platform: Why are try

Answer 1

I think people really overestimate the performance cost of throwing exceptions. Yes, there's a performance hit, but it's relatively tiny.

I ran the following test, throwing and catching a million exceptions. It took about 20 seconds on my Intel Core 2 Duo, 2.8 GHz. That's about 50K exceptions a second. If you're throwing even a small fraction of that, you've got some architecture problems.

Here's my code:

using System;
using System.Diagnostics;

namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            Stopwatch sw = Stopwatch.StartNew();
            for (int i = 0; i < 1000000; i++)
            {
                try
                {
                    throw new Exception();
                }
                catch {}
            }
            Console.WriteLine(sw.ElapsedMilliseconds);
            Console.Read();
        }
    }
}