[K12OSN] K12LTSP Server Specs

[Mella]

Modern workstation as LTSP server?

Intel(R) Core(TM)2 Duo CPU     E6550  @ 2.33GHz or better (Quadcore)
3-4GB DRAM
SATA2 or better HDD. (30MB /boot, 6-10GB for system /, 2GB swap) 
(OOO.org, Gnome, KDE, ICEWM, Firefox, Thunderbird)
1Gbit LAN
K12LTSP based on FC6/Centos5/RHEL5/32bit (need first install on older 
chipset (P4 or less) + kernel update to 2.6.22 (yum update kernel*) )
K12LTSP based on FC6/Centos5/RHEL5/64bit (need first install on older 
chipset (I instelled on P4 3GHz) + kernel update to 2.6.22 from 
http://download.fedora.redhat.com/pub/fedora/linux/core/updates/6/x86_64/kernel-2.6.22.14-72.fc6.x86_64.rpm)

Serves maximum 20 (15 optimal) clients (OOO.org, firefox, thunderbird, 
Acroread, Gaim. Icewm + Kdesktop)

I use separate server (dualxeon with PCI-X) for /home over NFS - 3ware 
SATA2 RAID 5 + Gbit LAN. (3 LTSP servers behind).

Main bottleneck is communication between RAM and CPU. I removed one of 
the dualchannel memory and server's speed reduced dramatically.
There is even no need for quadcore CPU, because usually clients in 
normal office environment do not use such CPU critical apps. Only reason 
for Quadcore is in case, when one of processes "goes mad" and uses 99% 
of core. (sometimes I saw it on 32bit FC6)  
Increasing number of clients is not rasonable, because increasing CPU or 
RAM do not remove or rise bottleneck. Also, 32bit kernel can use on 
modern C2D motherboards only 3.2GB of RAM. 64bit kernel uses all memory. 
Byt, I repeat, usually there is no need for more than 3GB, because 15 
concurrent clients use approximately 2-2.6GB of RAM. Beginning of 2.4G 
(with 3GB of RAM), FC6 start swapping.
(maybe modern C2D or C2Q server motherboards can handle over 3.2GB RAM 
on 32bit system)

Now (March 2008) I use K12 EL5 64bit (centos 5) on C2D E6550 with 4GB 
RAM  - 15 concurrent clients. I'm happy!

Mella