Hi
> Moodle version: 1.9.4
The later versions of Moodle 1.9 were more streamlined than the early 1.9 releases and all the 2.x versions. Update Moodle to 1.9.latest (1.9.16 right now).
MySQL: 5.0.5
Isn't that old? On mysql.com the "community server" is in 5.5 now. Debian 6 comes with 5.1.
BTW, what is you platform? By any chance Microsoft Windows?
> Our processor is Intel Pentium 4 CPU 2.66GHz and we have 1.5 GB RAM at present.
Single core, single thread? Sounds like a couple of years old desktop.
> We will be conducting a quiz on Moodle with 100 students logging in at once. In the past, we have had issues with large numbers of students logging in at once.
> Do you suggest we increase the RAM as well, and if so how much?
If those 100 students log in at once to take an online exam, your server is definitely too weak.
As already mentioned you must at least get more RAM. RAM is cheap today. Once you go beyond
4 GB you will need a 64 bit operating system. If Windows, forget desktop versions (XP, Vista,
Windows 7) and get at least Server 2003. Linux is definitely more efficient, if you know how.
If you are really tight on hardware going back to Moodle 1.6 could be an option, its quiz engine
was the most efficient I've seen.
Check the initial information given in the introduction to this forum (Hardware and Performance),
read the performance documentation and the FAQ. Search the forum as explained there or
go through recent discussions, for example
http://moodle.org/mod/forum/discuss.php?d=195439.