On Fri, 22 Jun 2018, Alan Cox wrote: > > The other point is a quite pointless assumption that existing scrollback is > > "optimized". Even vgacon mostly uses software scrollback these days, as the > > amount of VGA display memory is really small. > > All of our console driver code is horribly unoptimized for most of > todays hardware. Long ago I did look at what was needed but it's a > seriously non-trivial change. In particular > > - Console I/O occurs under enough locks to keep fort knox safe. That > means it's very very hard to accelerate > > - The logic is plain wrong for a lot of modern video. We shouldn't be > scrolling, we should be rendering the current backing text buffer at > video refresh rate or similar and if the source of the updates outruns > us it doesn't matter - we don't have to draw all the glyphs as if we > were fast enough they would have been a blur anyway.
My executive summary from what you say is that there is no longer an advantage to maintain a central vga-style glyph buffer in the core console code, right? Nicolas
