This is going to be a verry short comparision of the two Json-serialization frameworks:
Json.Net – http://json.codeplex.com
ServiceStack.Text – https://github.com/mythz/ServiceStack.Text

I have always used Json.Net when dealing with serialization of entities back and forth to Json, but then I stumbled upon this: “Fastest JSON Serializer for .NET released” – http://www.servicestack.net/mythz_blog/?p=344 Man was I excited, since I need the “best” performance I can get for this in SisoDb (http://www.sisodb.com)

Lets do a simple test

I just downloaded latest version of both libraries (Json.Net – changeset: 57577), (ServiceStack.Text – changeset: c3e5d0c, v1.8), compiled them for .Net 4.0 Client profile and put together a very simple example. Note, I’m not testing features here, just raw serialization and deserialization. I don’t know if you can “tweak” ServiceStack.Text as much as you can with Json.Net, e.g: Strategies for null property handling, missing member, indentation of Json etc.

Item being serialized

[Serializable]
public class Customer
{
    public int Id { get; set; }

    public int CustomerNo { get; set; }

    public string Firstname { get; set; }

    public string Lastname { get; set; }

    public ShoppingIndexes ShoppingIndex { get; set; }

    public DateTime CustomerSince { get; set; }

    public Address BillingAddress { get; set; }

    public Address DeliveryAddress { get; set; }

    public Customer()
    {
        ShoppingIndex = ShoppingIndexes.Level0;
        BillingAddress = new Address();
        DeliveryAddress = new Address();
    }
}

[Serializable]
public class Address
{
    public string Street { get; set; }

    public string Zip { get; set; }

    public string City { get; set; }

    public string Country { get; set; }

    public int AreaCode { get; set; }
}

[Serializable]
public enum ShoppingIndexes
{
    Level0 = 0,
    Level1 = 10,
    Level2 = 20,
    Level3 = 30
}

Timer application

static void Main(string[] args)
    {
        var numberOfCustomers = 100000;
        var numberOfItterations = 5;

        //Console.WriteLine("Json.Net");
        //TimeSerializationAction(
        //  SerializeUsingJsonNet, numberOfCustomers, numberOfItterations);
        //TimeDeserializationAction(
        //  Newtonsoft.Json.JsonConvert.SerializeObject, DeSerializeUsingJsonNet,
        //  numberOfCustomers, numberOfItterations);

        //Console.WriteLine("ServiceStack.Text");
        //TimeSerializationAction(
        //  SerializeUsingServiceStackText, numberOfCustomers, numberOfItterations);
        //TimeDeserializationAction(
        //  ServiceStack.Text.JsonSerializer.SerializeToString, DeserializeUsingServiceStackText, 
        //  numberOfCustomers, numberOfItterations);

        Console.ReadKey();
    }

    private static void SerializeUsingJsonNet(IEnumerable<Customer> customers)
    {
        var json = customers.Select(Newtonsoft.Json.JsonConvert.SerializeObject).ToList();
    }

    private static void DeSerializeUsingJsonNet(IEnumerable<string> json)
    {
        var customers = json.Select(
            Newtonsoft.Json.JsonConvert.DeserializeObject<Customer>).ToList();
    }

    private static void SerializeUsingServiceStackText(IEnumerable<Customer> customers)
    {
        var json = customers.Select(ServiceStack.Text.JsonSerializer.SerializeToString).ToList();
    }

    private static void DeserializeUsingServiceStackText(IEnumerable<string> json)
    {
        var customers = json.Select(
            ServiceStack.Text.JsonSerializer.DeserializeFromString<Customer>).ToList();
    }

    private static void TimeSerializationAction(
        Action<IList<Customer>> action, int numOfCustomers, int numOfItterations)
    {
        var stopWatch = new Stopwatch();

        for (var c = 0; c < numOfItterations; c++)
        {
            var customers = CustomerFactory.CreateCustomers(numOfCustomers);

            stopWatch.Start();
            action(customers);
            stopWatch.Stop();

            Console.WriteLine("TotalSeconds = {0}", stopWatch.Elapsed.TotalSeconds);

            stopWatch.Reset();
        }
    }

    private static void TimeDeserializationAction(
        Func<Customer, string> serializer, Action<IList<string>> action, int numOfCustomers, int numOfItterations)
    {
        var stopWatch = new Stopwatch();

        for (var c = 0; c < numOfItterations; c++)
        {
            var customerJsons = CustomerFactory.CreateCustomers(numOfCustomers).Select(serializer).ToList();

            stopWatch.Start();
            action(customerJsons);
            stopWatch.Stop();

            Console.WriteLine("TotalSeconds = {0}", stopWatch.Elapsed.TotalSeconds);

            stopWatch.Reset();
        }
    }
}

Results

Each step: Serialization and Deserialization; has been executed one scenario at a time for each framework. Doing serialization in one execution and deserialization in another. Each time five itterations with 100000 customers in each itteration.

Scenarios: Serialization and Deserialization for:

• Running debug mode with debugger – (This value is not representative since this isn’t how an application will be deployed)
• Running debug mode without debugger – (This value is not representative since this isn’t how an application will be deployed)
• Running release mode without debugger – (These are the measurements I would use for comparison, since this is how my deployed application would run)

Measurements

Json.Net vs ServiceStack.Text - Values

Average values

Json.Net vs ServiceStack.Text - Average values

Now you can decide for your self. I will continue with ServiceStack.Text, especially since deserialization is of greater importance for my project: SisoDb.

Download the example code and Excel with the results.

//Daniel