Memory remapping with 8GB RAM

[vm_ws]

Hi All,

On my new computer with 8GB RAM BIOS initially only showed 7103MB available.

I turned on memory remap function and now it shows the full 8192MB.

Since address space of PCI devices is now moved above 4GB limit, would that cause any problems if I install Windows 2003 Ent 32-bit? Or do I need 64-bit version?

For 32-bit version, do I need the /PAE turned on, and if yes, how can I do it during installation - or should I install OS with 7.1GB, add /PAE and only then turn on remap?

I really don't want to give up a whole 1GB, please help.

[continuum]

You got a 8 GB RAM host and wanna run a 7 GB VM - crazy ...

Anyway - 2k3 enterprise edition will have no problems.

You cannot run such large amounts of RAM inside a VM without having to back the memory with swap - so what is the use of setting RAM so high ?

You maybe able to run a 4 GB VM with keeping all virtual-memory allocated in real RAM so that may be turn out to be much, much faster ....

[surferdave]

Why not just run Windows directly on the box. With that amount of RAM dedicated to the guest, there would only be enough room for on VM anyway.

[vm_ws]

I will not be running a single VM using all the RAM - it'll be 8-12 VMs

My main concern is do I need a 64 bit Windows 2003 Enterprise as a host or 32-bit Windows 2003 will work OK despite the fact that address space of all devices is now above 4GB

[surferdave]

The VMkernel will handle the memory addressing. Using 32-bit Windows 2003 will work fine since it does not directly access the physical memory.

[KevinG]

The VMware Workstation can only use the memory that the host reports as available.

[surferdave]

Okay, I thought you meant the host already has seen the full 8GB of memory. You are correct that what the host sees, this is the only thing that can be allocated to the guest.

I would load W2K3 64 to get all of the RAM out of your box. If you use 32-bit W2K3 servers, their memory will be managed by the VMkernel therefore giving you the max memory for each guest machine.

[surferdave]

Correction, the guest OS can be W2K3 32-bit since the VMkernel will handle the physical memory.

[KevinG]

VMkernel

This is Workstation not ESX

[surferdave]

Similar to the VMkernel in ESX, but the VMM (virtual machine monitor) which runs the physical hardware interface.

[vm_ws]

Let me rephrase the question:

Is using the "memory remap" BIOS feature is safe for a Windows 2003 32 bit host?

[surferdave]

Yes. I would enable it first before the OS install. If you already have an image with W2K3 32 running, I would enable it in the BIOS and use PAE on the OS.

If you are going to run 8 different VMs, then using memory remap or PAE will not really do much for you. The minimum to run W2K3 32 is 384 MB. Even if you ran 7 VMs with the minimum that would only leave you with around 2GB left for an above average VM.

[vm_ws]

Do I need to use "AWE" and "4GT" with the "PAE" switch?

I don't understand your calculations. 7x384=2688. Why do you say it will leave me only around 2GB for another VM? 9192-2688=6504. Even after leaving 1GB for host and 512MB for Vmware overhead there is plenty to go around.