How does VMware manage memory?

Hey everyone, quick question. I have been playing around with Virtualbox and VMware on my laptop (Lenovo Ideapad Y500), and I was wondering how the memory was managed in VMware vs Virtualbox. It seems that Virtualbox allocates the memory you dedicate to a VM, where VMware seems to be taking it as needed. Is this the case or is there something wrong with my machine and the way it is reporting my memory usage? Using Vmware player 7.1.0 and Virtualbox 4.3.26 with Ubuntu Gnome 15.04

I'm not sure. I agree VirtualBox takes the ram when you start the VM. You have to be careful with ram because if a VM starts swapping out because you dont have enough ram both your Host and clients can come down to a crawl.

Im on Linux now but when I was on windows using both VBox and VMware I had a small swap file and tried to never let RAM get to the point I had to swap out programs.

Here you have an article about memory virtualization in VMware ESXi: Memory virtualization ESXi

For VirtualBox, like Marten said, it takes RAM when a VM is started: Memory management VirtualBox

Yes, when ever you initialize the hyper-visor it uses the amount of ram you specify the vm to handle into swap space.

I think that a type-2 where you install vmware on top of an OS doesn't allow memory sharing - what you allocate to the virtual machine is not available to your primary OS or other virtual machines as soon as you start the VM.

A type-1 install where vmware is installed on bare metal and all other OS's are installed on top of that can allow for dynamic resource allocation, including memory.

That's all "book knowledge" though. I haven't done either installation myself, and dynamic resource allocation may not be feature that is readily available (free).