What size does the server have to give to each response chunk?

Question

If I wanted to configure my personal server so that the response for a certain request is set according to the chunk rules : what size should each of the server response chunk have?

For example, let's say that the chunked response is a long HTML page or a file.

How would you behave in these two cases?

Answer 1

From the RFC :

This allows dynamically produced content to be transferred...

In other words: Transfer-Encoding: chunked is needed when the length of content is unknown .

The length of your content may be as big as 10Tb... but also it can be as small as 10 bytes. It doesn't matter. The chucks' sizes depend solely on the algorithms you are using to generate them and to read then.

Let's say you generate a stream of messages of different lengths, one character per second. In this case you can decide to send one byte chucks to the client. This way the client will be able to use the data as soon as it arrives. But if your client have no use for partial messages, then you probably should save the bandwidth and send a chunk at the moment you've finished generating the next message. And again it doesn't matter how big or small the message is. It can be 2 characters or it can be 1000.

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On second thought, there are some use cases for Transfer-Encoding: chunked with the data of known size. But then your question becomes to broad to answer. It depends on your client code, server code, network conditions, data properties, desired user experience, etc.

And if by any chance you are asking about optimal size from the network perspective, then just send the whole file - that the best bet. And support Content-Range on your server instead of Transfer-Encoding: chunked .