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Oh do you have details on this? I recall doing this on an older machine and I would get an 80x25 terminal. Now when I do it, I get a high-res display. I gues

by chubot 9y ago

Oh do you have details on this? I recall doing this on an older machine and I would get an 80x25 terminal. Now when I do it, I get a high-res display. I guess the latter is in graphics mode? It definitely has slow throughput at catting files, e.g. if I cat the output of "seq 100000". The latency seems better though. Probably not as good as text mode. I honestly don't know what text/console mode even is. I know there is a VGA "spec" -- I think all graphics drivers for PC-compatible devices have to support VGA and text mode? Or is it part of the BIOS?

cat199 9y ago
Not an expert, but basically 'text mode' entails something like directly putting the text characters into a memory buffer, and the monitor rendering those in hardware via onboard fonts.
TheDong 9y ago
The resolution change is likely the result of Kernel Mode Setting (KMS). This is the ability for the linux kernel itself to set the resolution of the display, among other things. The easiest way to turn it off is to add "nomodeset" to your kernel commandline. The correct term, by the way, is not "text mode", but rather "a virtual console" or "virtual tty" or such. Hopefully that gives you enough search terms to learn more.
- JdeBP 9y ago
  Actually, the correct term is text mode. It is precisely whether the display hardware is operating in text mode or graphics mode that is the subject of discussion here. With the hardware in text mode, even without CRTC tricks, scrolling is relatively fast compared to graphics mode. Scrolling the display in graphics mode involves shifting much more data around, as does rendering individual characters. The confusion arises because people, as you have done, erroneously conflate the kernel virtual terminals with "text mode". In fact, the norm nowadays is for kernel virtual terminals to use graphics mode. It permits a far larger glyph repertoire and more colours, for starters, as well as things like software cursors that can be a wider range of shapes and sprites for mouse pointers.

by chubot 9y ago

cat199 9y ago

Not an expert, but basically 'text mode' entails something like directly putting the text characters into a memory buffer, and the monitor rendering those in hardware via onboard fonts.

TheDong 9y ago

The resolution change is likely the result of Kernel Mode Setting (KMS). This is the ability for the linux kernel itself to set the resolution of the display, among other things. The easiest way to turn it off is to add "nomodeset" to your kernel commandline. The correct term, by the way, is not "text mode", but rather "a virtual console" or "virtual tty" or such. Hopefully that gives you enough search terms to learn more.

JdeBP 9y ago
Actually, the correct term is text mode. It is precisely whether the display hardware is operating in text mode or graphics mode that is the subject of discussion here. With the hardware in text mode, even without CRTC tricks, scrolling is relatively fast compared to graphics mode. Scrolling the display in graphics mode involves shifting much more data around, as does rendering individual characters. The confusion arises because people, as you have done, erroneously conflate the kernel virtual terminals with "text mode". In fact, the norm nowadays is for kernel virtual terminals to use graphics mode. It permits a far larger glyph repertoire and more colours, for starters, as well as things like software cursors that can be a wider range of shapes and sprites for mouse pointers.