Best way(s) to speed up lab?

[Andy Figueroa]

Harry, for comparison, our setup is less demanding than yours, since I have
fewer users, but I also have less RAM in my server, so it may make for a
reasonable comparison.  We don't experience "workstation lagging" for which
I am very thankful.

Very standard Edubuntu setup Ubuntu 8.04 LTS updated regularly.
We're using a Dell server with two scsi drives, four cores of Intel XEON
2.40GHz and 4 gigs of ram.
The seven workstations are diskless Compaqs with P3s running 667 MHZ and 256
megs or RAM through a 100 mb switch.

Even when all seven workstations are going, and Firefox is normally the
first app the kids go for, everybody seems to be having a good computing
experience.

Your 20 users may be a lot more demanding on your network and your four CPU
cores than my 7.  You can readily see how your CPU is loaded and what your
RAM is doing by running "top" from the command line.

The LTSP environment has a tendency to keep stale processes running
interminably when students either crash an app or don't properly log off.  I
run a script hourly to kill all the processes owned by ordinary users that
are not currently logged in.  Since I started doing that, everybody's user
experience has improved as has with server stability.  There was a
discussion here a couple of months ago about the various programs/scripts
different system admins run to kill off stale processes.

I do not have a web server, mail server, or database running on the LTSP
server.  All the server does server the kids that are using it.

Andy Figueroa

Harry Sweet wrote:
> Hi all;
> 
> Going into the year, I hope to be able to solve workstation lagging problems once and for all.  I'm not sure where
> the bottleneck is as no swapping happens, and network thruput looks ok.  But I often get lagging when a full class is on.
> 
> 9.04 64 bit Ubuntu
> 
> Server = intel quad core, 8 gig ram, SATA drive, server box has a gigibit ethernet but the switch is 100.
> It also runs the classes web server, very lightly used and along with that Mysql, again not very busy and not used at
> all in most classes.
> 
> 20 Workstations are all 10 year old Ibm's, 256k ram.
> 
> Which of these things would likely improve performance the most?
> 
> 1.  Reinstall the server version of Ubuntu  
> 2.  Lose the GUI on the server or at least drop Gnome for something faster
> 3.  Run Firefox as a local app
> 4.  Get a gigabit switch to replace our 10 year old 100meg switch.
> 5.  Raid or SCSI disks
> 6.. Something I haven't thought of .....
> 
> 
> thanks
> 
> Harry Sweet
> Goshen High School
> Goshen, NY
>