VMWare and Server 03

[dnuggett]

So I am looking at setting up a networked environment at home.

One physical box. 3 Server 03 installs using VMWare for two. The physical machine will be the file server/storage box, one of the virtual machines will be the DC and the other an email server. My main question is how is memory managed in VMWare? I am trying to plan out how much I'll need. My thought initally was 3GB but if VMWare actively manages the RAM I can install 1GB and allocate it across all the machines at 1GB each letting VMWare decide what it needs and when. Is that feasible?

 

[MercenaryForHire]

You really want to avoid having the VM's share RAM.

Since you're just setting this up for home, is there any particular reason you're going the virtualization route rather than a "one box to rule them all" approach - other than the inherent L33tness of the former?

- M4H

 

[dnuggett]

Originally posted by: MercenaryForHire
You really want to avoid having the VM's share RAM.

Since you're just setting this up for home, is there any particular reason you're going the virtualization route rather than a "one box to rule them all" approach - other than the inherent L33tness of the former?

- M4H

Technically isn't the RAM shared anyway? I just set a Vista box in VMWare and gave it 1GB. Under task manager for the host box it shows it is using 400MB out of 2.5GB available (pf not included). How does this change when another VM is added besides just upping the host boxes usage to what one of or all of the VMs are using at the time?

As for why I'd go the VM route I want them as seperate machines for testing purposes, remote access and various other reasons.

 

[dnuggett]

Anybody out there know?

 

[skace]

I've never tried carving overlapping amounts of memory across VMs. Sounds ugly as all hell IMO.

 

[dnuggett]

So to wrap it up in order to have 2 VMs allocated 1 GB each the host needs to have at least at least 2GB of physical memory plus whatever you want to host unit to have?

 

[DarkTXKnight]

VMware and MS Virtual server each allocate as much RAM to a virtual machine as you tell it to. There is no "sharing " per se. For example if you have a 2 GB host machine and want the VM to have 1 GB to itself, then that will be dedicated to only that VM while it is working. To the host mahcine the 1GB of ram is completely comitted to the VM and the host will therefore act as if there is 1 GB of RAM to work with. In order for your setup to work, you will need to have at least 3 GB of physical ram on the host, then dedicate 1 GB of ram to each machine. You will then have 3 machines each with 1 GB of their own RAM

 

[dnuggett]

Originally posted by: DarkTXKnight
VMware and MS Virtual server each allocate as much RAM to a virtual machine as you tell it to. There is no "sharing " per se. For example if you have a 2 GB host machine and want the VM to have 1 GB to itself, then that will be dedicated to only that VM while it is working. To the host mahcine the 1GB of ram is completely comitted to the VM and the host will therefore act as if there is 1 GB of RAM to work with. In order for your setup to work, you will need to have at least 3 GB of physical ram on the host, then dedicate 1 GB of ram to each machine. You will then have 3 machines each with 1 GB of their own RAM

Then why isn't the set VM RAM allocated as used on the host machine? It appears it is shared.


Anyone have any concrete experience or VM pdfs or docs to point towards? I couldn't find anything on their forums.

 

[ktwebb]

I'd have to look at your setup. With VMWare the VM will get what you allocate when you set it up. If you give it a Gig, it will show a gig in Task manager or whatever memory manager your using. I'd have to boot up my never used MS virtual server to check on that statement for MS's offering. And I don't have any experience with GSX but ESX definitely gives what you allocate. So does workstation.

With ESX there is a sharing involved if you have multiple VM's allocated more than the available physical memory. So if I have 8GB in the box and have 6 VM's with 1.5GB each, then ESX will dynamically shift memory where needed most.

 

[Smilin]

Don't starve your host of RAM at the expense of the guests. You'll massacre your performance.