thehyperadvisor,

I think I understand what you are saying -- there is a major choice to be made right at the beginning of the process: whether to run an OS (such as WinServer2008 or what not) with a layered VM solution (such as VM Server) or whether to run ESXI as the OS on the server.

For the sake of the discussion, lets assume that the choice is to run an OS+app(VM Server or equivalent). The reason being that in the future the server providing the virtualization for the classroom's 21 net-appliances would be tasked with other activities outside of class hours. In this case I'm going to assume the OS choice will be WinServer2008.

Currently in the classroom we have 21 net appliances+21 monitors+21 keyboards+21 mice+ethernet hookups to a server whose specs I don't have at the moment. The installation is about 1.5 to 2 years old and is currently unworkable. I am told that in the first two to three months it was installed, the performance was decent. Since then, its been horribly slow and laggy.

The net appliance only has graphics controller, BIOS, 2 open USB ports and 2 connections for mouse/keyboard as well as the VGA-out connector and the ethernet port.

My curiosity is that if one assumes a classroom configuration as described, wherein all but the graphics processing has to be done on the server, how heavy a server do you have to have to adequately serve 21 simultaneous users each running a fair number of apps running in each VM (3x internet explorer + 2x office 2007 apps or 2x IE and MS Visual Studio 2008; this representing typical max load given the classes held in the classroom.) Each VM would be running windows-XP.

What I am trying to figure out is whether the server assigned to handle the classroom has the adequate basic hardware to potentially handle the load by asking "what SHOULD the server have?". After an initial reading of some VM-docs I get the impression that RAM would have to be well over 50+GB to allow for 2GB RAM per VM +vm-overhead +OS requirements. The remaining question in my mind is really CPU power. I have not had any practical experience in judging how well these Apps run when assigned varous amounts of mHZ-processing as VM is capable of doing...

For instance, in the Intel realm: Dual-Xeon quad cores (how fast) or dual-xeon-6core? Intel does not appear to offer 4x-xeon-quad or 4x-6cores. In theory I understand that one has to add up the total amount of Hz-processing available and then subtract OS requirements, then the remaining can be assigned to the individual VMs. So to put it another way: how many mhz do I need to assign for each VM to perform adequately in the above scenario?

Or do I need to step above the typical intel-motherboard into a whole different class of mother-board processor?

Thanks in advance,

Joseph

thehyperadvisor,

Thanks for the replies, they are much appreciated!

I have actually tried talking to the people in charge of the servers, but unfortunately it is something that they don't want to get into. As I am only a student (and not an employee of the IT department) its not something they want to get into details with me. Its something of a hot-potato, no one wants to wade into it.

As I mentioned in the beginning, this is more of an intellectual exercise on my part-- to figure out how such a scenario "should" be implemented rather than necessarily an attempt to fix the current situation (its not my job... and my meddling really might not be appreciated!)

Does VMware allow for dynamic allocation of resources based on demand? The impression I got from the ESXI / VM server docs was that each VM had to have an amount pre-assigned to it, but I am not even close to finishing my reading...My calculation was based on avoiding hard-faults as much as possible, providing each VM the necessary RAM to run a fair number of apps. In particular to allow for enough RAM for 21 instances of MS-visual studio to operate simultaneously, etc.

If VMware is able to reallocate on the fly along the lines of: "VM(1) is not logged on, so not assign max_amount... distribute to VM(2 through 10 that are logged on)" then that would be a whole different story. In any case I'll continue reading up on it.

Thanks again!

-Joseph

thehyperadvisor,

Thanks again! Yeah, that sounds very cool. The funny thing about VM is that its bringing me flashbacks to the early 90s-- I remember using an IBM 4381 mainframe running VM/CMS; a few years later the machine was decommissioned. In essence each terminal was a virtual machine with its own allocation of RAM defined at login, as well as a logical disk partition from the huge disk-platters back then. The CPU was timeshared. Then workstations and PCs took over...

In a sense we are coming back full circle to the idea of a mainframe to recapture efficiency in TCO. I find the idea very appealing, I loved playing with big iron!

I'm going to get a few old computers together, network them into a newer one here at home and start playing with VM, I think that will answer a lot of the questions I have.

-Joseph