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Memory Over-Committing (Erl, Naserpour)

How can multiple virtual servers be hosted on a single host when the virtual servers’ aggregate memory exceeds the physical memory that is available on the host?

Memory Over-Committing

Problem

A host needs to be able to host multiple virtual servers, even though their total memory configuration exceeds the host’s own physical memory.

Solution

Memory virtualization is implemented to enable more virtual servers to be hosted on the same host, by allowing the host’s physical memory to be exceeded by the total memory configuration of the virtual servers.

Application

One or more memory over-commitment components are implemented.
Memory Over-Committing: Virtual Servers A, B, and C are each allotted a portion of Host A’s physical memory.

Virtual Servers A, B, and C are each allotted a portion of Host A’s physical memory.

Memory Over-Committing: The four steps involved in applying the Memory Over-Committing pattern are shown.

The four steps involved in applying the Memory Over-Committing pattern are shown.

Memory Over-Committing: Virtual Servers A through F can all be powered on at Hypervisor A.

Virtual Servers A through F can all be powered on at Hypervisor A.