Text consoles and framebuffer consoles in Linux
And the second post by Chris Siebenmann, this time about how the Linux console has gotten slower over the years.
If you've been running x86 Linux servers for long enough, you've probably noticed two changes in the kernel's text console. On the one hand, the text console has gotten substantially bigger, sporting sizes like 128*40 instead of the much smaller old sizes, for example 80*25. On the other hand, text output to the console has generally gotten slower, usually much slower than you would expect for the change in console size. These two changes are not unrelated, because they are both part of a fundamental change in how the kernel console normally worked and works on x86 hardware.
Hint: the two posts are related.