No dedicated memory allocation options for VM usage in VM player

Having dedicated memory allocation for VM usage is useful for both increasing the performance of your VM(s) and security. The reason for this is that without it memory resources are swapped by default as part of your main host OS system memory. This also means that it will also be subject to the main host swap file system between the RAM and the hard drive which requires even more additional read/write access time between the RAM and disk drive causing it to slows the whole process down even further. This can cause VM's to run less smoothly when more demanding tasks are running and you might not have enough processing power at your disposal to compensate as determined by the processor in your machine. e.g. VM's that maybe require more memory to be given over to video rendering for example where you might find video performance to be a bit choppy in your VM.

In VMware workstation you can assign a portion of your system memory for dedicated VM usage and disallow swapping between your host OS system memory allocated portion and the VM(s) allocated portions. This in essence will make your VM(s) run like it has its own independent RAM and swap file which in turn will make it run much faster if you're using a regular mechanical hard drive (provided its fast enough and has sufficient cache memory). But if you're lucky enough to have a fast SSD it wouldn't really make too much of a difference whether you implemented this or not. In such instances it might only serve to boost security by keeping your host instance memory management and VM memory management separate. This is ideal for sandboxing and testing purposes. Especially of the kind where you know potential unwanted programs and viruses could be sneaked onto the system to allow for unwanted additional access or causes potential system failure on your main local host instance of your OS. It will keep your main host instance a little safer from any potential threats. 

Its also generally a good idea to not assign more then the recommended upper limit for your host  machine as this will also degrade overall VM and system performance on the host system. 

As far as I'm aware there are no options to partition and allocate dedicated memory portions for VM usage in Virtualbox either, but I'll confirm this later after some additional testing of it.

Random related fact:

Did you know VMware is built using Linux just like Virtualbox?