I have a result set that will never exceed 500; the results that come back from the web-service are assigned to a search results object.

The data from the webservice is about 2mb; the bit I want to use is about a third of each record, so this allows me to cache and quickly manipulate it.

I want to be able to sort and filter the results with the least amount of overhead and as fast as possible so I used the VCSKICKS timing class to measure their performance

              Average        Total (10,000)
Type       Create  Sort      Create  Sort
HashSet    0.1579  0.0003    1579    3
IList      0.0633  0.0002    633     2
IQueryable 0.0072  0.0432    72      432

Measured in Seconds using http://www.vcskicks.com/algorithm-performance.php

I created the hashset through a for loop over the web-service response (adding to the hashset).

The List & IQueryable were created using LINQ.

Question I can understand why HashSet takes longer to create (the foreach loop vs linq); but why would IQueryable take longer to sort than the other two; and finally is there a better way to assign the HashSet.

Thanks

Actual Program

public class Program
{
    private static AuthenticationHeader _authHeader;
    private static OPSoapClient _opSession;
    private static AccommodationSearchResponse _searchResults;

    private static HashSet<SearchResults> _myHash;
    private static IList<SearchResults> _myList;
    private static IQueryable<SearchResults> _myIQuery;

    static void Main(string[] args)
    {
        #region Setup WebService
        _authHeader = new AuthenticationHeader { UserName = "xx", Password = "xx" };
        _opSession = new OPSoapClient();


        #region Setup Search Results

        _searchResults = _opgSession.SearchCR(_authHeader, "ENG", "GBP", "GBR");

        #endregion Setup Search Results

        #endregion Setup WebService


        // HASHSET
        SpeedTester hashTest = new SpeedTester(TestHashSet);
        hashTest.RunTest();
        Console.WriteLine("- Hash Test \nAverage Running Time: {0}; Total Time: {1}", 
            hashTest.AverageRunningTime, 
            hashTest.TotalRunningTime);

        SpeedTester hashSortTest = new SpeedTester(TestSortingHashSet);
        hashSortTest.RunTest();
        Console.WriteLine("- Hash Sort Test \nAverage Running Time: {0}; Total Time: {1}",
            hashSortTest.AverageRunningTime,
            hashSortTest.TotalRunningTime);

        // ILIST
        SpeedTester listTest = new SpeedTester(TestList);
        listTest.RunTest();
        Console.WriteLine("- List Test \nAverage Running Time: {0}; Total Time: {1}",
            listTest.AverageRunningTime,
            listTest.TotalRunningTime);

        SpeedTester listSortTest = new SpeedTester(TestSortingList);
        listSortTest.RunTest();
        Console.WriteLine("- List Sort Test \nAverage Running Time: {0}; Total Time: {1}",
            listSortTest.AverageRunningTime,
            listSortTest.TotalRunningTime);

        // IQUERIABLE
        SpeedTester iqueryTest = new SpeedTester(TestIQueriable);
        iqueryTest.RunTest();
        Console.WriteLine("- iquery Test \nAverage Running Time: {0}; Total Time: {1}",
            iqueryTest.AverageRunningTime,
            iqueryTest.TotalRunningTime);

        SpeedTester iquerySortTest = new SpeedTester(TestSortableIQueriable);
        iquerySortTest.RunTest();
        Console.WriteLine("- iquery Sort Test \nAverage Running Time: {0}; Total Time: {1}",
            iquerySortTest.AverageRunningTime,
            iquerySortTest.TotalRunningTime);
    }

    static void TestHashSet()
    {
        var test = _searchResults.Items;

        _myHash = new HashSet<SearchResults>();

        foreach(var x in test)
        {
            _myHash.Add(new SearchResults
                                     {
                                         Ref = x.Ref,
                                         Price = x.StandardPrice
                                     });
        }

    }

    static void TestSortingHashSet()
    {
        var sorted = _myHash.OrderBy(s => s.Price);
    }



    static void TestList()
    {
        var test = _searchResults.Items;

        _myList = (from x in test
                   select new SearchResults
                              {
                                  Ref = x.Ref,
                                  Price = x.StandardPrice
                              }).ToList();
    }

    static void TestSortingList()
    {
        var sorted = _myList.OrderBy(s => s.Price);
    }

    static void TestIQueriable()
    {
        var test = _searchResults.Items;

        _myIQuery = (from x in test
                     select new SearchResults
                                {
                                    Ref = x.Ref,
                                    Price = x.StandardPrice
                                }).AsQueryable();

    }

    static void TestSortableIQueriable()
    {
        var sorted = _myIQuery.OrderBy(s => s.Price);
    }

}