Ubuntu kernel memory management

[Riaan Bredenkamp]

Currently running Ubuntu on a ltsp server, X86 architecture, 4 GiB RAM. 
Free reports the following:

admin at tuxlab:~$ free
            total       used       free     shared    buffers     cached
Mem:       3108492    1339980    1768512          0     222352     808256
-/+ buffers/cache:     309372    2799120
Swap:      2650684          0    2650684

using:

admin at tuxlab:~$ uname -a
Linux tuxlab 2.6.10-6-686-smp #1 SMP Wed May 3 17:18:12 UTC 2006 i686 
GNU/Linux

So, it seems like the Kernel is splitting the virtual memory into the 
traditional 3G user-space 1G kernel-space, as is described at: 
http://kerneltrap.org/node/2450

* Is this the most optimal way to physical memory available to the system?
* If not, what would be and how would I go about implementing it?


Thanks
Riaan