Memory is a precious resource for most environments, isn't it? Thus, the efficient use of memory should be achieved by tuning it. The first rule in optimizing KVM memory performance is not to allocate more resources to a guest during setup than it will use!
We will discuss the following in greater detail:
Memory allocation
Memory tuning
Memory backing
Let us start by how to allocate memory for a virtual system or guest. To make the allocation process simple, we will consider the libvirt client virt-manager again. Memory allocation can be done from the window shown in the following screenshot.
As you can see in the preceding figure, there are two main options: Current allocation and Maximum allocation: