Load Balancing "Apache + MySQL" for online exams!

I am new to this field of load balancing and would require some help.
We have a PHP + MySQL based online exam software which conducts simple
online exams (in the form of Multiple Choice Answers). The software
uses MySQL backend and Apache web server. We had a mock test and
realised that the minute the number of students logging in increased to
beyond 30, the computer became slow and finally couldn't withstand it.
Beyond 30 students sitting at once the PHP pages failed to load and
students couldn't log in. Luckily this was the mock exam!!

The solution as we got from our Computer Science faculty is "load
balancing". We are willing to setup multiple servers hosting Apache and
let students log in. The current solution we thought of was that make
batches of 30 students and make them connect to one server, etc. But
then we are dealing with 500 students. And it is not liable to do
something like this.

We also heard about DNS Load Balancing. Will this help? The issue is we
don't want a student's test answers to be stored in various computers.
It should be that once a student connects to one server, he should be
on that server itself. (We don't mind replicating all the databases of
Questions/Answers as well as students' info on all the server
computers)

If DNS load balancing is not the solution, then is LVS (Linux Virtual
Server) the right answer? If yes, which LVS (we went through the site
to find various versions of LVS (LVS- NAT or LVS-TUN or LVS-DR?).
We have Red Hat Linux 9 installed on the computers. Will LVS work with
them?

Thanking you in advance,
Wishing everyone a happy and prosperous New Year,


PS : I am a student in my 3rd year and have taken up an elective (in
college) of implementing "New Load Balancing Algorithms". Could anyone
please mention a framework/API on which I could implement these new
"load balancing" algorithms written by my Sir? Am well conversant with
C/C++/Perl.

On 2006-12-23, Roshan Sumbaly <(E-Mail Removed)> wrote:
> realised that the minute the number of students logging in increased to
> beyond 30, the computer became slow and finally couldn't withstand it.

30 concurrent users? Unless your system is a 8080 with 4 Kb of ram,
I'd say that you have some problems in the connection tracking.

Davide

--
I never really understood how there could be things that would drive you
insane just because you knew them until I run into Windows.
--Peter da Silva on alt.sysadmin.recovery

In comp.os.linux.networking Davide Bianchi <(E-Mail Removed)>:
> On 2006-12-23, Roshan Sumbaly <(E-Mail Removed)> wrote:
>> realised that the minute the number of students logging in increased to
>> beyond 30, the computer became slow and finally couldn't withstand it.

> 30 concurrent users? Unless your system is a 8080 with 4 Kb of ram,
> I'd say that you have some problems in the connection tracking.

Seconded, there is something completely wrong with the setup.

The OP might like to get someone who knows what he is doing to
login and drill down the problem to what it is about. Running sar
should give first hints without checking manually all time,
though it might just be obvious from 'dmesg'/'free'/'top' and
alike?

Still we don't know anything about the system in question, though
it sounds the OP "Computer Science faculty" suggestion isn't
that clever...

--
Michael Heiming (X-PGP-Sig > GPG-Key ID: EDD27B94)
mail: echo (E-Mail Removed) | perl -pe 'y/a-z/n-za-m/'
#bofh excuse 191: Just type 'mv \* /dev/null'.