A serializer comparison of different libraries in Dart

Hive Serializer
Flatbuffers
Message Pack
Isar (TODO)

Infos I used the VSCode extension Dart Data Class Generator to generate data classes and modified the fromMap and toMap methods a bit. I removed the keys of type string and replaced them with plain integers.

The Dart classes can be found under lib/models as well as the Hive generated adapters. The model generated by flatbuffers can be found under lib/flatbuffers/models_models_generated.dart.

The Model:

{
  'age': 40,
  'firstSeen': 'ep1',
  'house': 'Lannister',
  'name': 'Tyrion',
  'actor': {
    'birthCity': 'Morristown',
    'dateOfBirth': -17625600000, //DateTime(1969, 6, 11).millisecondsSinceEpoch
    'name': 'Peter Dinklage',
  },
}

Note [Edit]: all MessagePack toMap or fromMap where first using integer as keys and not string keys as regular json. That is why there encoding size is so much smaller compared to their json version. This was changed below when added also FlexBuffers.

I used dart2native to compile to machine code and run the test in a loop and to average them out. My CPU Intel i9-9900k:

running compiled

Runs 10:
Hive                             Types.encode        96 bytes :       45.1 average ticks
Hive                             Types.decode        96 bytes :       20.9 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :       34.5 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :        2.5 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :       31.5 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :        2.1 average ticks
Message Pack                     Types.encode        70 bytes :       70.2 average ticks
Message Pack                     Types.decode        70 bytes :       23.5 average ticks

Runs 100:
Hive                             Types.encode        96 bytes :      25.14 average ticks
Hive                             Types.decode        96 bytes :      16.83 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :      29.88 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :       2.01 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :      27.81 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :       1.84 average ticks
Message Pack                     Types.encode        70 bytes :       54.8 average ticks
Message Pack                     Types.decode        70 bytes :      19.57 average ticks

Runs 1000:
Hive                             Types.encode        96 bytes :     18.787 average ticks
Hive                             Types.decode        96 bytes :     23.846 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :     23.287 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :      1.354 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :     23.424 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :      1.325 average ticks
Message Pack                     Types.encode        70 bytes :     41.673 average ticks
Message Pack                     Types.decode        70 bytes :     14.372 average ticks

running in vm

Runs 10:

Hive                             Types.encode        96 bytes :     5232.0 average ticks
Hive                             Types.decode        96 bytes :     2203.1 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :     3785.6 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :      494.6 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :      858.4 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :       16.1 average ticks
Message Pack                     Types.encode        70 bytes :     3916.2 average ticks
Message Pack                     Types.decode        70 bytes :     2099.2 average ticks

Runs 100:

Hive                             Types.encode        96 bytes :     693.16 average ticks
Hive                             Types.decode        96 bytes :     441.76 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :     672.85 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :      67.45 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :     366.19 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :      13.96 average ticks
Message Pack                     Types.encode        70 bytes :      791.9 average ticks
Message Pack                     Types.decode        70 bytes :     443.23 average ticks

Runs 1000:

Hive                             Types.encode        96 bytes :    151.505 average ticks
Hive                             Types.decode        96 bytes :    118.854 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :    162.797 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :     20.825 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :    109.985 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :     10.055 average ticks
Message Pack                     Types.encode        70 bytes :    267.008 average ticks
Message Pack                     Types.decode        70 bytes :     126.68 average ticks

Thoughts:

I am not 100% convinced, that those measurements reflects the real performance.
I only can say, that flatbuffers do take the most bytes. While debugging, flatbuffers had a lot of 0 bytes in the ByteData buffer.
Also, using flatbuffers ObjectBuilder took may more time, when running via the VM, then the BuffersBuilder. But when compiled the ObjectBuilder on average was faster.
Obviously, they are some runtime optimizations, thats happening. The decode methods for flatbuffers bytes for the ObjectBuilder and the BufferBuilder is actually the exact same method. So by does it take longer, when decode a byte using ObjectBuilder?

Update 15.07.2020

Added encoding via Flexbuffer
Added MessagePack en/decoding when Map<String, dynamic>
Added MessagePack en/decoding when Map<int, dynamic>

Runs 1000:

Hive                             Types.encode        70 bytes :     19.707 average ticks
Hive                             Types.decode        70 bytes :     18.647 average ticks
Flatbuffers objectBuilder        Types.encode       160 bytes :     26.845 average ticks
Flatbuffers objectBuilder        Types.decode       160 bytes :      1.517 average ticks
Flatbuffers buffersBuilder       Types.encode       160 bytes :     29.244 average ticks
Flatbuffers buffersBuilder       Types.decode       160 bytes :      1.289 average ticks
Message Pack with toMap Json     Types.encode       123 bytes :     53.601 average ticks
Message Pack with fromMap Json   Types.decode       123 bytes :     24.704 average ticks
Message Pack map, int keys       Types.encode        67 bytes :     21.645 average ticks
Message Pack map, int keys       Types.decode        67 bytes :     14.965 average ticks
FlexBuffers build from Object    Types.encode       200 bytes :     83.324 average ticks
FlexBuffers Reference Object     Types.decode       200 bytes :      1.965 average ticks
FlexBuffers build into Vector    Types.encode       130 bytes :     41.927 average ticks
FlexBuffers build into Map       Types.encode       154 bytes :     59.077 average ticks

commands to compile flatbuffers

.\flatc.exe --dart -o .\lib\models -I .\idl .\idl\monster.fbs

.\flatc.exe --dart --gen-mutable --schema -b -o .\lib\models -I .\idl .\idl\models.fbs

Manuelbaun/serializer_libs_comparison

A serializer comparison of different libraries in Dart

Update 15.07.2020

commands to compile flatbuffers