Installation guide

CHAPTER 6 Administering ESX Server
255
Memory
• Private — total memory allocated to virtual machines that is not shared
• Shared — total memory allocated to virtual machines and securely shared with
other virtual machines
• Swapped — total memory forcibly reclaimed from virtual machines and stored
in system swap files
• Balloon Driver — memory reclaimed from virtual machines by cooperation with
the VMware Tools (vmmemctl driver) and guest operating systems
This is the preferred method for reclaiming memory from virtual machines, since
it reclaims the memory that is considered least valuable by the guest operating
system. The system “inflates” the balloon driver to increase memory pressure
within the virtual machine, causing the guest operating system to invoke its own
native memory management algorithms. When memory is tight, the guest
operating system decides which particular pages of memory to reclaim, and if
necessary, swaps them to its own virtual disk. This proprietary technique
provides predictable performance that closely matches the behavior of a native
system under similar memory constraints.
• Unused — memory that has never been accessed by the virtual machines, and
consequently has not yet been allocated
• Total — total memory allocated to virtual machines
Virtual Machines: Virtual Machine Name
For each running virtual machine, this chart includes a breakdown of the virtual
machine's memory allocation:
• RAM — maximum amount of memory configured for use by the guest
operating system running in the virtual machine. This value is often larger than
the actual amount of memory currently allocated to the virtual machine, which
may vary depending on the current level of memory overcommitment
• Private — memory allocated to the virtual machine that is not shared
• Shared — memory allocated to the virtual machine that is shared
• Swapped — memory forcibly reclaimed from the virtual machine and stored in
the system swap files
• Balloon Driver — memory reclaimed from virtual machines by cooperation with
the VMware Tools (vmmemctl driver) and the guest operating system
• Unused — memory that has never been accessed by the virtual machine, and
consequently has not yet been allocated