Photoshop :: Terminal Services

We are installing photoshop on Win 2003 server running terminal services. We have about 15 students per server. I was wondering when setting the system performance on memory usage is the setting on a global scale or on per-user.

Sample: 4gigs ram adobe default setting is is about 50 to 55% of total ram leaving about 2 gigs left. Now how will photoshop handle the memory if 21 users were using the system at the same time. Would that 2 gig be divvied out to each user who ever is needing more at that time get more memory?

I am asking this because there is talk about setting the memory of PS lower to around 300 megs under each student profile. So that the student will not use more than allowed. Does photoshop recognize unique performance settings per user in terminal services? OR does PS see system performance settings as a global change, remember we have only one instance installed of PS and that is a server.