yeah you'll only see 4gb there, last year I had a similar setup both on 32 bit, except Red Hat and Apache, 1000 users at exam time is plausable and I always found the the DB was the bottle neck, I tried the performance tweaks in this forum but the load was just too much, I see your going for clustering on the DB will this be active/active using master-master or what way are you planning it?
This year I'm on 4 nodes, 2 for the web front end and two for the database, I'm replicating the database using master slave but am too afraid to do master/master and have clients loadbalanced over the two, so its just a hot standby that the load balancer will switch to if it doesn't hear a heartbeat for the master.
I have a question related to the load balancing over two http servers- what are the moodle applcation requirements here? there is some stuff on clustering in this forum but nothing relates to the application itself-
e.g do you have to rsync a single moodle install across both servers - do any files in /moodle change?
do you install a single moodle app in a shared location(san)?
what about file locking in /moodle & /moodledata?
Install 2 moodle apps (same build) and keep /moodledata on san and use sticky sessions?
Sorry don't mean to hijack the thread, I'm seeing a massive speed increase this year using 64bit RHEL for both db and httpd, with only 4gb ram, I'd recommend using a software loadbalancer for the DB if its going to be an active active cluster.
Rob.
