Command buffer is slow?

[metaphist]

I pulled 2.0 and started to modify things in the samples folder to test features. All went well until I tried the command buffer.

Originally I was testing the event bus to trigger a source generated query from a key stroke. That all went fine, but when I tried adding a missing component outside the query via command buffer, all of sudden the event locked everything up for seconds (with 150k entities).

To rule out my changes, I went back to the original sample code and changed the bulk add/remove entity example to use the command buffer instead of world directly - this indeed locks up the system on each update. From what I can see, the add seems to be the culprit, not the playback.

Is this expected?

public sealed class ColorSystem : SystemBase<GameTime>
{
    private readonly QueryDescription _entitiesToChangeColor = new QueryDescription().WithAll<Sprite>();
    private static GameTime? _gameTime;
    private static Random _random;
    private CommandBuffer _commandBuffer;

    public ColorSystem(World world)
        : base(world)
    {
        _random = new Random();
        _commandBuffer = new CommandBuffer();
    }

    public override void Update(in GameTime time)
    {
        _gameTime = time;

        // Modifies the color of all entities fitting the entitiesToChangeColor query.
        World.Query(in _entitiesToChangeColor, (Entity e, ref Sprite sprite) =>
        {
            sprite.Color.R += (byte)(_gameTime.ElapsedGameTime.TotalMilliseconds * 0.08);
            sprite.Color.G += (byte)(_gameTime.ElapsedGameTime.TotalMilliseconds * 0.08);
            sprite.Color.B += (byte)(_gameTime.ElapsedGameTime.TotalMilliseconds * 0.08);

            // A demonstration of bulk adding and removing components.
            // World.Add(in _entitiesToChangeColor, _random.Next());
            // World.Remove<int>(in _entitiesToChangeColor);
            _commandBuffer.Add(e, _random.Next());
            _commandBuffer.Remove<int>(e);
        });

        _commandBuffer.Playback(World);
    }
}