XenServer memory overview
XenServer memory usage is based on how much physical memory exists on the server itself.
In the first chapter of the book, we have discussed the Resource Pools concepts and introduced the "Control Domain" virtual machine, also known as "Dom0".
Dom0 is a small and privileged virtual machine that Xen hypervisor loads when a host running XenServer starts up. The control domain runs the management tool stack and also provides low-level services to other VMs, such as providing physical access to devices.
When calculating the memory that XenServer uses, there are two components to consider. First is the memory that the XenServer virtualization engine known as Xen hypervisor uses. Second is the memory that the control domain uses.
Xen hypervisor uses a fixed amount of memory. This value is set to 128 MB. The Dom0 uses a variable amount of memory based on the total physical memory on the server.
The Dom0 reserves a minimum of 200 MB of memory, but does not use more than 752...
