I am running Ubuntu Server on VirtualBox. I am not using X Windows, only the command line. It looks like it is redrawing the screen for every line that causes the screen to shift down. In other words if there is empty space on the screen below the current line, it works normally, but if the current line is at the bottom of the screen, when the system moves to the next line it refreshes the whole screen line by line. This causes the system to run very slowly because I have to wait for the whole screen to refresh for every line and it hits the CPU at 90%.
I installed Debian Lenny in VirtualBox and it didn't do this.
Why does Ubuntu Server redraw the screen for each line? Is there a way to make this behaviour go away?
Update:
I am running Ubuntu Server 10.04.
I found another solution to disable the framebuffer. I added blacklist vga16fb to /etc/modprobe.d/blacklist-framebuffer.conf.
ls -l /boot:
total 14268
-rw-r--r-- 1 root root 640617 2010-04-16 06:01 abi-2.6.32-21-generic
-rw-r--r-- 1 root root 115847 2010-04-16 06:01 config-2.6.32-21-generic
drwxr-xr-x 3 root root 4096 2010-06-07 17:38 grub
-rw-r--r-- 1 root root 7957975 2010-06-07 17:36 initrd.img-2.6.32-21-generic
-rw-r--r-- 1 root root 160280 2010-03-23 02:37 memtest86+.bin
-rw-r--r-- 1 root root 1687378 2010-04-16 06:01 System.map-2.6.32-21-generic
-rw-r--r-- 1 root root 1196 2010-04-16 06:03 vmcoreinfo-2.6.32-21-generic
-rw-r--r-- 1 root root 4029792 2010-04-16 06:01 vmlinuz-2.6.32-21-generic
Best Answer
Your framebuffer is enabled. Certain framebuffer configurations are not accelerated and will use the CPU to redraw the screen - in effect turning your CPU in to a bitblit engine when it decides to "scroll" the text. Disable it using the instructions found here, which will "tell" VirtualBox that you want "text" and not "graphics".