FBDEV Console Patches Optimize Performance - Print Directory Listing ~25% Faster

[ypnos]

Glad to see scrolling coming back. When I noticed it was removed it as a real WTF moment...

Don't rejoice too soon. Scrolling is a feature of the vt, this is only about fbdev. The optimization here is related to how fast the whole screen scrolls up when a new line is appended. Not about manual scrolling which was removed due to security concerns.

[uxmkt]

I don't know how I feel about this. I really hoped the lack of maintainer and loss of functionality would finally give impetus to a userspace solution. Personally, I use kmscon with hwaccel, it's okay, fast enough, looks okay, but really isn't a complete solution and feels unfinished.

There were/are two movements. One is adding more cruft to the most basic non-serial terminal you can get with Linux, and the other is removing cruft from a proper graphics stack.
In the blue corner: There once was the venerable VGA text console. Then hardware started providing a pixel framebuffer, and Linux went to combine its text terminal (vt.c) code with fbdev. Then someone made fbterm, a userspace graphical console bolted onto /dev/fb0. And later, kmscon using the same idea, but now with truetype support.
In the red corner: the old fat X server, with an xterm (or god forbid, a bloated, laggy program, possibly with some GL to produce the looks of a curved surface monitor flickering its green phosphors). Then a lot of fat was cut, so to speak, with Wayland. Make the terminal fullscreen, you could almost forget there even was a Wayland session.
The red option is almost as lightweight as the blue option now being fat. And at least for me, that explain's the stopped work on kmscon.

[david-nk]

Still very slow. It takes 0.1s with gnome-terminal and of that only 0.03s are spent in user-space, the rest is spent in the kernel actually finding the files.