HttpServer and HttpClient are slow at processing HTTPS data

[Tienisto]

HttpClient and HttpServer are slow at processing large binary data when HTTPS is enabled.

I have created a repository to test this: https://github.com/Tienisto/httpserver-benchmark

In general, the HTTP performance is fine. But there is a strange behaviour when dealing with encryption (HTTPS).
Dart is much slower than Node.js which is actually noticable in one of my projects: localsend/localsend#384 where someone even created a Rust backend because of the poor Dart performance: https://github.com/tom8zds/localsend_rs

On Windows or macOS, this is not really noticable because they are often fast enough so that the bandwidth is the bottleneck (and not Dart).
On Android or older iPhones however, this is definitely noticable.

Here are the results (they ran on a M2 chip):

HTTP

Client	Server	Speed (more is better)	Factor
Dart	Dart	1641 MB/s	1x
Node.js	Dart	1655 MB/s	1x
Dart	Node.js	2270 MB/s	1.38x
Node.js	Node.js	2177 MB/s	1.33x

HTTPS

Client	Server	Speed (more is better)	Factor
Dart	Dart	170 MB/s	1x
Node.js	Dart	158 MB/s	0.92x
Dart	Node.js	272 MB/s	1.6x
Node.js	Node.js	1228 MB/s	7.22x

[mraleph]

Duplicate of #54009

[mraleph]

Let's take discussion there.

[Tienisto]

I have created rhttp that can be used in the mean time. Currently, it requires Flutter but if #50565 is resolved, this package can be used in native Dart also.