Compress the data

To optimize further, we have to understand how data is represented.

Bits are essentially switches in our computers, used to represent all of the data. A boolean, for example, can be stored with just a single bit. But for more complex data, we have to use more bits, where each combination of the bits represent different data. It's important to note that bits are stored in groups of 8, called bytes. For this reason, we can't go below 8 bits per data element, and we are also forced to use increments of 8 — for example, a boolean will actually take up 8 bits (1 byte) due to this.

If we look closer at the bits, we often find unnecessary ones. For example, by default in Luau (Roblox's programming language), every number is stored as a Float64. Float meaning it can contain decimals, and 64 meaning it uses 64 bits to store the number. Since there's no U in front, that means it's signed, meaning it can store negative values too. The issue is that we don't need negative values, decimals, or 64 whole bits, to store the number 1, for example.

A Float64 can store numbers all the way down to -1.7976931348623157 x 10^308 and all the way up to 1.7976931348623157 x 10^308, with up to about 16 decimal digits. In many cases, that's overkill. Therefore, we can lower the amount of bits used to store the data.

One example of this optimization, is the Tween+ server tween identifiers, which are intentionally limited to the range 0-255, because that's the range of a Uint8 (unsigned 8-bit integer). This means that there can be no more than 256 server tweens at once, but also means reduced network usage.

And it doesn't just have to be numbers you reduce in size — it can be all sorts of data types.

But there's specific data that is often overlooked. You see, every time we send something over the network on Roblox for example, we also send the identifier for the event, so that the client knows which event we're talking about — for example, we might have to inform the client that we're firing the StartTween event — that's what happens behind the scenes when you fire a RemoteEvent in Roblox. Therefore, it's best to minimize the amount of event fires.

If we just send everything through the same event, we can just fire that one event no more than 1 time a frame by combining all of the data, allowing us to store the event identifiers how we want, which can result in slightly reduced network usage if multiple events fire in the same frame.

These optimizations, along with even more, are included in Packet, a Luau network library, which Tween+ utilizes.