C语言中整数除法与双除法#

using System;
using System.Collections.Generic;
using System.Diagnostics;    

namespace MainProgram
{
    static class Program
    {
        static void Main()
        {
            const int intCount = 9999999;
            const double doubleCount = (double)intCount;

            List<int> integerList = new List<int>();
            List<double> doubleList = new List<double>();

            Random r = new Random();

            for (int i = 0; i < intCount; i++)
            {
                int intt = r.Next(1, 100);

                integerList.Add(intt);
                doubleList.Add(intt);
            }

            Stopwatch intWatch = new Stopwatch();

            intWatch.Start();

            for (int i = 0; i < intCount; i++)
            {
                integerList[i] = integerList[i] / intCount;
            }

            intWatch.Stop();

            Console.WriteLine($"Int Execution Time: {intWatch.ElapsedMilliseconds} ms");

            ///////////////////////////////////////////
            Stopwatch doubleWatch = new Stopwatch();

            doubleWatch.Start();

            for (int i = 0; i < doubleCount; i++)
            {
                doubleList[i] = doubleList[i] / doubleCount;
            }

            doubleWatch.Stop();

            Console.WriteLine($"Double Execution Time: {doubleWatch.ElapsedMilliseconds} ms");

            Console.ReadLine();
        }
    }
}

输出:

Int Execution Time: 114 ms
Double Execution Time: 108 ms

我有两个问题:

1. 此测试代码是否反映了正确的测试代码?
2. 如果测试代码是正确的,为什么double类型花费的时间更少?

// * Summary *

BenchmarkDotNet=v0.10.12, OS=Windows 10.0.18362
Intel Core i7-3520M CPU 2.90GHz (Ivy Bridge), 1 CPU, 4 logical cores and 2 physical cores
  [Host]     : .NET Framework 4.6.1 (CLR 4.0.30319.42000), 32bit LegacyJIT-v4.8.4220.0  [AttachedDebugger]
  DefaultJob : .NET Framework 4.6.1 (CLR 4.0.30319.42000), 32bit LegacyJIT-v4.8.4220.0


 Method |     Mean |      Error |     StdDev |   Median | Rank |     Gen 0 |     Gen 1 |     Gen 2 | Allocated |
------- |---------:|-----------:|-----------:|---------:|-----:|----------:|----------:|----------:|----------:|
  Test1 | 375.3 ms |  0.7270 ms |  0.6801 ms | 375.2 ms |    1 | 3937.5000 | 3937.5000 | 3937.5000 | 128.01 MB |
  Test2 | 509.6 ms | 10.6781 ms | 30.1178 ms | 496.5 ms |    2 | 4937.5000 | 4937.5000 | 4937.5000 | 256.01 MB |

// * Warnings *
Environment
  Summary -> Benchmark was executed with attached debugger

// * Hints *
Outliers
  DateParserBenchmark.Test2: Default -> 7 outliers were removed

// * Legends *
  Mean      : Arithmetic mean of all measurements
  Error     : Half of 99.9% confidence interval
  StdDev    : Standard deviation of all measurements
  Median    : Value separating the higher half of all measurements (50th percentile)
  Rank      : Relative position of current benchmark mean among all benchmarks (Arabic style)
  Gen 0     : GC Generation 0 collects per 1k Operations
  Gen 1     : GC Generation 1 collects per 1k Operations
  Gen 2     : GC Generation 2 collects per 1k Operations
  Allocated : Allocated memory per single operation (managed only, inclusive, 1KB = 1024B)
  1 ms      : 1 Millisecond (0.001 sec)

// * Diagnostic Output - MemoryDiagnoser *


// ***** BenchmarkRunner: End *****
// * Artifacts cleanup *

Test1() 是整数, Test2() 是双倍的。