Linux Internals

There are a lot of things that I have found hard to find out about Linux and many things I end up having to peice together and guess a conclusion. This page has no real direction, like my many other pages, but will be a starting point to collect things that I thought could use some more explaining so they will ususally come with a reference site. If you here I assume you already know what it is you want and do not take time to explain it.

  1. Enabling Core Dumps
  2. Grub2 Notes
  3. ATi Crossfire

Enabling Core Dumps

Reference: HOWTO enable core-dumps

Enabling core dumps makes use of the ulimit command.

$ ulimit -c (MAX blocks)

This only enables it for you current working shell, for system wide you can read the referenced page. Or if you just want it for any shell you open you can place the command in ~/.bashrc

The ulimit command is also useful for viewing/modifying other system limits. Run the following command to view the limits.

$ ulimit -a

Grub2 Notes

Reference: Makeing Grub2 recognize other OS
Slash Images with Grub2
Grub2 doesn't see my Windows Partition
This is most likely because you are missing os-prober.
# aptitude install os-prober
# update-grub
How do I change the background image
What I will ask you to edit searches in:
Edit /etc/grub.d/05_debian_theme line 16 such that filename is the name of the file you want.
for i in {/boot/grub,/usr/share/images/desktop-base}/filename.{png,tga} ; do

ATi Crossfire

Reference: No Hybrid Crossfire

I have not found any performance improvements with Hybrid Crossfire. This code was taking from the referenced page by HeikoH

aticonfig --initial --adapters=all -f # this forces a new configuration
aticonfig --lsa               # this now shows two adapters, the HD3200 and the HD3450
                              # it also shows a number for each adapter (probably 0 and 1)
aticonfig --lscc              # the crossfire candidates, shows also both adapters

aticonfig --cfa --adapter=0,1 # in this case card 0 is the master card,
                              # card 1 is the slave card. I think I use
                              # the HD3450 as the master card, so check
                              # with aticonfig --lscc which number it has

aticonfig --cf=on --adapter=0 # again, in case the mastercard of the chain
                              # has number 0 assigned, this should enable
                              # crossfire on the next start of Xorg

# after rebooting:
aticonfig --lsch              # this should show the crossfire chain using
                              # both graphics cards, and it should be
                              # enabled