Fastest way to serialize and deserialize .NET objects

Here's your model (with invented CT and TE) using protobuf-net (yet retaining the ability to use XmlSerializer, which can be useful - in particular for migration); I humbly submit (with lots of evidence if you need it) that this is the fastest (or certainly one of the fastest) general purpose serializer in .NET.

If you need strings, just base-64 encode the binary.

[XmlType]
public class CT {
    [XmlElement(Order = 1)]
    public int Foo { get; set; }
}
[XmlType]
public class TE {
    [XmlElement(Order = 1)]
    public int Bar { get; set; }
}
[XmlType]
public class TD {
    [XmlElement(Order=1)]
    public List<CT> CTs { get; set; }
    [XmlElement(Order=2)]
    public List<TE> TEs { get; set; }
    [XmlElement(Order = 3)]
    public string Code { get; set; }
    [XmlElement(Order = 4)]
    public string Message { get; set; }
    [XmlElement(Order = 5)]
    public DateTime StartDate { get; set; }
    [XmlElement(Order = 6)]
    public DateTime EndDate { get; set; }

    public static byte[] Serialize(List<TD> tData) {
        using (var ms = new MemoryStream()) {
            ProtoBuf.Serializer.Serialize(ms, tData);
            return ms.ToArray();
        }            
    }

    public static List<TD> Deserialize(byte[] tData) {
        using (var ms = new MemoryStream(tData)) {
            return ProtoBuf.Serializer.Deserialize<List<TD>>(ms);
        }
    }
}

A comprehansive comparison between diffreent formats made by me in this post- https://maxondev.com/serialization-performance-comparison-c-net-formats-frameworks-xmldatacontractserializer-xmlserializer-binaryformatter-json-newtonsoft-servicestack-text/

Just one sample from the post- enter image description here


Having an interest in this, I decided to test the suggested methods with the closest "apples to apples" test I could. I wrote a Console app, with the following code:

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Threading.Tasks;

namespace SerializationTests
{
    class Program
    {
        static void Main(string[] args)
        {
            var count = 100000;
            var rnd = new Random(DateTime.UtcNow.GetHashCode());
            Console.WriteLine("Generating {0} arrays of data...", count);
            var arrays = new List<int[]>();
            for (int i = 0; i < count; i++)
            {
                var elements = rnd.Next(1, 100);
                var array = new int[elements];
                for (int j = 0; j < elements; j++)
                {
                    array[j] = rnd.Next();
                }   
                arrays.Add(array);
            }
            Console.WriteLine("Test data generated.");
            var stopWatch = new Stopwatch();

            Console.WriteLine("Testing BinarySerializer...");
            var binarySerializer = new BinarySerializer();
            var binarySerialized = new List<byte[]>();
            var binaryDeserialized = new List<int[]>();

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var array in arrays)
            {
                binarySerialized.Add(binarySerializer.Serialize(array));
            }
            stopWatch.Stop();
            Console.WriteLine("BinaryFormatter: Serializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var serialized in binarySerialized)
            {
                binaryDeserialized.Add(binarySerializer.Deserialize<int[]>(serialized));
            }
            stopWatch.Stop();
            Console.WriteLine("BinaryFormatter: Deserializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);


            Console.WriteLine();
            Console.WriteLine("Testing ProtoBuf serializer...");
            var protobufSerializer = new ProtoBufSerializer();
            var protobufSerialized = new List<byte[]>();
            var protobufDeserialized = new List<int[]>();

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var array in arrays)
            {
                protobufSerialized.Add(protobufSerializer.Serialize(array));
            }
            stopWatch.Stop();
            Console.WriteLine("ProtoBuf: Serializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var serialized in protobufSerialized)
            {
                protobufDeserialized.Add(protobufSerializer.Deserialize<int[]>(serialized));
            }
            stopWatch.Stop();
            Console.WriteLine("ProtoBuf: Deserializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);

            Console.WriteLine();
            Console.WriteLine("Testing NetSerializer serializer...");
            var netSerializerSerializer = new ProtoBufSerializer();
            var netSerializerSerialized = new List<byte[]>();
            var netSerializerDeserialized = new List<int[]>();

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var array in arrays)
            {
                netSerializerSerialized.Add(netSerializerSerializer.Serialize(array));
            }
            stopWatch.Stop();
            Console.WriteLine("NetSerializer: Serializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);

            stopWatch.Reset();
            stopWatch.Start();
            foreach (var serialized in netSerializerSerialized)
            {
                netSerializerDeserialized.Add(netSerializerSerializer.Deserialize<int[]>(serialized));
            }
            stopWatch.Stop();
            Console.WriteLine("NetSerializer: Deserializing took {0}ms.", stopWatch.Elapsed.TotalMilliseconds);

            Console.WriteLine("Press any key to end.");
            Console.ReadKey();
        }

        public class BinarySerializer
        {
            private static readonly BinaryFormatter Formatter = new BinaryFormatter();

            public byte[] Serialize(object toSerialize)
            {
                using (var stream = new MemoryStream())
                {
                    Formatter.Serialize(stream, toSerialize);
                    return stream.ToArray();
                }
            }

            public T Deserialize<T>(byte[] serialized)
            {
                using (var stream = new MemoryStream(serialized))
                {
                    var result = (T)Formatter.Deserialize(stream);
                    return result;
                }
            }
        }

        public class ProtoBufSerializer
        {
            public byte[] Serialize(object toSerialize)
            {
                using (var stream = new MemoryStream())
                {
                    ProtoBuf.Serializer.Serialize(stream, toSerialize);
                    return stream.ToArray();
                }
            }

            public T Deserialize<T>(byte[] serialized)
            {
                using (var stream = new MemoryStream(serialized))
                {
                    var result = ProtoBuf.Serializer.Deserialize<T>(stream);
                    return result;
                }
            }
        }

        public class NetSerializer
        {
            private static readonly NetSerializer Serializer = new NetSerializer();
            public byte[] Serialize(object toSerialize)
            {
                return Serializer.Serialize(toSerialize);
            }

            public T Deserialize<T>(byte[] serialized)
            {
                return Serializer.Deserialize<T>(serialized);
            }
        }
    }
}

The results surprised me; they were consistent when run multiple times:

Generating 100000 arrays of data...
Test data generated.
Testing BinarySerializer...
BinaryFormatter: Serializing took 336.8392ms.
BinaryFormatter: Deserializing took 208.7527ms.

Testing ProtoBuf serializer...
ProtoBuf: Serializing took 2284.3827ms.
ProtoBuf: Deserializing took 2201.8072ms.

Testing NetSerializer serializer...
NetSerializer: Serializing took 2139.5424ms.
NetSerializer: Deserializing took 2113.7296ms.
Press any key to end.

Collecting these results, I decided to see if ProtoBuf or NetSerializer performed better with larger objects. I changed the collection count to 10,000 objects, but increased the size of the arrays to 1-10,000 instead of 1-100. The results seemed even more definitive:

Generating 10000 arrays of data...
Test data generated.
Testing BinarySerializer...
BinaryFormatter: Serializing took 285.8356ms.
BinaryFormatter: Deserializing took 206.0906ms.

Testing ProtoBuf serializer...
ProtoBuf: Serializing took 10693.3848ms.
ProtoBuf: Deserializing took 5988.5993ms.

Testing NetSerializer serializer...
NetSerializer: Serializing took 9017.5785ms.
NetSerializer: Deserializing took 5978.7203ms.
Press any key to end.

My conclusion, therefore, is: there may be cases where ProtoBuf and NetSerializer are well-suited to, but in terms of raw performance for at least relatively simple objects... BinaryFormatter is significantly more performant, by at least an order of magnitude.

YMMV.