6.7

If a virtual machine has high ballooning or swapping, check the amount of free physical memory on the
host. The host might require more memory resources. If it does not, check the resource shares,
reservation, and limit of the virtual machines and resource pools on the host. Verify that the host settings
are adequate and not lower than those set for the virtual machine.
If memory usage is high or you notice degradation in performance, consider taking the following actions.
Table 1‑114. Memory Performance Enhancement Advice
# Resolution
1 Verify that VMware Tools is installed on each virtual machine. The balloon driver is installed with VMware Tools and is critical
to performance.
2 Verify that the balloon driver is enabled. The VMkernel regularly reclaims unused virtual machine memory by ballooning and
swapping. Generally, this does not impact virtual machine performance.
3 Reduce the memory space on the virtual machine, and correct the cache size if it is too large. This frees up memory for other
virtual machines.
4 If the memory reservation of a virtual machine is set to a value much higher than its active memory, decrease the reservation
setting so that the VMkernel can reclaim the idle memory for other virtual machines on the host.
5 Migrate one or more virtual machines to a host in a DRS cluster.
6 Add physical memory to the host.
Memory (MB)
The Memory (MB) chart displays memory data counters for virtual machines.
This chart is located in the Home view of the virtual machine Performance tab. It appears only at
collection levels 2, 3, and 4.
In the following descriptions, the guest physical memory refers to the virtual-hardware memory presented
to a virtual machine for its guest operating system. Machine memory is actual physical RAM in the host.
Note that not all counters are collected at collection level 1.
vSphere Monitoring and Performance
VMware, Inc. 90