Cant allocate the full 3.5GB to a virtual Machine

[Rachael]

I'm runnung an AMD Phenom 9850 Black Edition with 8GB of memory. My host OS is kubuntu 8.04 (Hardy Heron) 32-bit with the server kernel so I have access to all 8GB memory. If I set a virtual machine to use 3.5GB of memory as it now allows as its maximum, when I boot into the VM it produces an error saying it is unable to allocate enough memory as the host is running low on resources and it pauses the VM. Doing a quick check using top shows I still have plenty of free memory.

[Frank Mehnert]

It is very unlikely that you will be able to allocate 3.5GB RAM for a VM running as 32-bit Linux process. Note that the maximum size available for user code is 3.5GB but this includes the program code and all libraries as well. I assume the upper limit for 32-bit Linux is somewhere between 2.5GB and 3GB. With Windows in normal mode the limit is less than 2GB. Running a server kernel does not mean that you are able to assign more than 4GB virtual memory to one process. It means that the PAE mode of the CPU is used to be able to address more than 4GB physical memory. Of course VBox should not offer the option to set the RAM to 3.5GB when running on a 32-bit kernel.

[Frank Mehnert]

Note that starting with VirtualBox 2.2.0, you can assign up to 16GB of memory to a guest on 64-bit hosts. There is no way to improve this on a 32-bit system without rewriting a big part of the VMM. Therefore closing.