6.0.1

Table 1‑15. Data Counters (Continued)
Chart Label Description
Granted Sum of the guest physical memory granted for all powered on virtual machines.
Granted memory is mapped to the host's machine memory.
Granted memory for a host includes the shared memory of each virtual machine on
the host.
n
Counter: granted
n
Stats Type: Absolute
n
Unit: Megabytes (MB)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 2 (4)
Swap Used Sum of the memory swapped by all powered on virtual machines on the host.
n
Counter: swapused
n
Stats Type: Absolute
n
Unit: Megabytes (MB)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 2 (4)
Total Aggregate total memory available to the cluster.
n
Counter: totalmb
n
Stats Type: Absolute
n
Unit: Megabytes (MB)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
Chart Analysis
To ensure best performance, the host memory must be large enough to accommodate the active memory of
the virtual machines. The active memory can be smaller than the virtual machine memory size. This allows
you to over-provision memory, but still ensures that the virtual machine active memory is smaller than the
host memory.
Transient high-usage values usually do not cause performance degradation. For example, memory usage
can be high when several virtual machines are started at the same time or when a spike occurs in virtual
machine workload. However, a consistently high memory usage value (94% or greater) indicates that the
host is probably lacking the memory required to meet the demand. If the active memory size is the same as
the granted memory size, the demand for memory is greater than the memory resources available. If the
active memory is consistently low, the memory size might be too large.
If the memory usage value is high, and the host has high ballooning or swapping, check the amount of free
physical memory on the host. A free memory value of 6% or less indicates that the host cannot handle the
demand for memory. This leads to memory reclamation, which might degrade performance.
If the host has enough free memory, check the resource shares, reservation, and limit settings 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 machines.
If the host has little free memory available, or if you notice a degradation in performance, consider taking
the following actions.
Table 1‑16. 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.
Chapter 1 Monitoring Inventory Objects with Performance Charts
VMware, Inc. 21