The latest version of Linux kernel, 2.6.25, introduces some enhancements in the memory management specifically addressing virtualization platform needs, as Linux Kernel Newbies is reporting:

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The memory resource controller isolates the memory behavior of a group of tasks -cgroup- from the rest of the system. It can be used to:

• Isolate an application or a group of applications. Memory hungry applications can be isolated and limited to a smaller amount of memory.
• Create a cgroup with limited amount of memory, this can be used as a good alternative to booting with mem=XXXX.
• Virtualization solutions can control the amount of memory they want to assign to a virtual machine instance.
• A CD/DVD burner could control the amount of memory used by the rest of the system to ensure that burning does not fail due to lack of available memory.

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The new Memory Resource Controller can impact the behaviour of hardware virtualization and OS virtualization platforms, as OpenVZ development team confirms with additional insights.