Quick'n'dirty Rust UI library startup time and binary size comparison

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Quick'n'dirty Rust UI library startup time and binary size comparison

Note: this is very much not a good scientific benchmark. Most things I only measured once and I didn't try to control compilation settings. I just cloned the repositories, and ran cargo run -r for an example that seemed fairly minimal to me. I only measured on one machine, on one OS. I still think there is a tiny bit of value in these measurements (hence this gist), but don't take them at face value!

UI lib/app	size	Final render	window	task bar
Slint	15MB	111ms	90ms	62ms
egui	12MB	118ms	-	21ms
Freya	28MB	146ms	-	14ms
Dioxus Blitz	37MB	220ms	-	70ms
Tessera	11MB	265ms	-	0ms
Floem	23MB	285ms	-	0ms
GPUI	23MB	313ms	-	208ms
Dioxus	9MB	480ms	285ms	258ms
Sublime Text	-	264ms	-	230ms
Zed	-	413ms	232ms	257ms

Explanation: I measured the time by recording my 144hz screen via OBS. I disabled animations in Gnome. I started the binary via gnome-terminal (via direct path, not cargo run) and then took the time difference between the first frame that the "enter" in the terminal was drawn and other points in time:

• "task bar": when the new window registered in the Gnome task bar
• "window": when the first bit of the window was visible. If it's the same as "final render", it's - and that's good as there are fewer visual jumps.
• "final render": when nothing was changing anymore (some libraries first rendered something incomplete or in the wrong color scheme).

Libraries:

• Slint: 85692d178, todo example
• egui: 28cbd73c5c0, hello_world example
• Freya: v0.3.4, button example
• Dioxus Blitz: Dioxus with the experimental Blitz backend. I cloned the blitz repo, 2044d690, flex example
• Tessera: tessera-ui-v2.1.0, counter example
• Floem: 6148cd8f, counter example
• GPUI: v0.2.0, hello_world example
• Dioxus: v0.6.3, hello_world example
• Sublime Text: not a library, just as comparison
• Zed: not a library, just as comparison. Zed is using gpui so it's weird that it manages to show a window (albeit not final render) quite a bit earlier than the gpui example.