WelcomeWelcome | FAQFAQ | DownloadsDownloads | WikiWiki

Author Topic: Xfbdev (tinyX) slow  (Read 161 times)

Offline fier

  • Newbie
  • *
  • Posts: 2
Xfbdev (tinyX) slow
« on: October 31, 2025, 11:45:52 AM »
Hello everyone! I'm running TCL on a Pentium III with a GeForce 6000 series card. I've noticed that certain operations like scrolling and resizing are really slow. It also happens if text has to scroll in xterm due to long output. All other operations are pretty fast.

This is quite annoying, because it's the main contributing factor to making this system feel slow to me. I theorize this happens because Xfbdev is trying to copy from the framebuffer directly, which might be slow on this hardware, for whatever reason (maybe it has to do with the PCI bus).

Official Xorg has (used to have?) something called ShadowFB, which, if I understand correctly, stores the framebuffer in RAM, so it can be read directly from there. Is there a way to enable this for Xfbdev? I tried searching for it some time ago but couldn't find it.

Perhaps there is some other solution I don't know of?

Any help would be much appreciated :)

Offline Juanito

  • Administrator
  • Hero Member
  • *****
  • Posts: 15309
Re: Xfbdev (tinyX) slow
« Reply #1 on: October 31, 2025, 12:24:44 PM »
Are things any better using Xvesa instead of Xfbdev?

Offline Rich

  • Administrator
  • Hero Member
  • *****
  • Posts: 12293
Re: Xfbdev (tinyX) slow
« Reply #2 on: October 31, 2025, 12:42:54 PM »
Hi fier
Welcome to the forum.

... Is there a way to enable this for Xfbdev? ...
The only option for Xfbdev is:
Code: [Select]
Xfbdev Device Usage:
-fb path         Framebuffer device to use. Defaults to /dev/fb0

However, Xvesa does appear to use a shadow framebuffer:
Code: [Select]
TinyX VESA Usage:
-mode         VESA video mode to use (Be careful!)
-listmodes    List supported video modes
-force        Attempt even unsupported modes
-no-shadow    Don't use a shadow framebuffer (default on) <-------------------
-nolinear     Never use linear framebuffer (Not useful)
-swaprgb      Use if colors are wrong in PseudoColor and 16 color modes
-map-holes    Use contiguous memory map (For seg fault with rare BIOS)
-verbose      Emit diagnostic messages during BIOS initialization
-force-text   Always use standard 25x80 text mode on server exit or VT switch
-boot         Soft boot video card

Offline Rich

  • Administrator
  • Hero Member
  • *****
  • Posts: 12293
Re: Xfbdev (tinyX) slow
« Reply #3 on: October 31, 2025, 12:46:24 PM »
Hi fier
Use Xvesa.tcz, not Xvesa-old.tcz.

Offline fier

  • Newbie
  • *
  • Posts: 2
Re: Xfbdev (tinyX) slow
« Reply #4 on: October 31, 2025, 01:04:47 PM »
Are things any better using Xvesa instead of Xfbdev?

However, Xvesa does appear to use a shadow framebuffer:
Code: [Select]
...

Oh, yes! Xvesa's much faster, thank you ;D