6.0.1

Table 1‑12. Disk I/O Performance Enhancement Advice (Continued)
# Resolution
11 For ESXi hosts, create virtual disks as preallocated. When you create a virtual disk for a guest operating system,
select Allocate all disk space now. The performance degradation associated with reassigning additional disk space
does not occur, and the disk is less likely to become fragmented.
12 Use the most current host hardware.
Memory (MB)
The Memory (MB) chart displays consumed memory for the cluster. The chart appears only at collection
level 1.
This chart is located in the Home view of the cluster Performance tab.
Table 1‑13. Data Counters
Chart Label Description
Consumed Amount of host machine memory used by all powered on virtual machines in the cluster. A
cluster's consumed memory consists of virtual machine consumed memory and overhead
memory. It does not include host-specific overhead memory, such as memory used by the
service console or VMkernel.
n
Counter: consumed
n
Stats Type: Absolute
n
Unit: Megabytes (MB)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
Total Total amount of machine memory of all hosts in the cluster that is available for virtual machine
memory (physical memory for use by the Guest OS) and virtual machine overhead memory.
Memory Total = Aggregate host machine memory - (VMkernel memory + Service Console
memory + other service memory)
NOTE The totalmb data counter is the same as the effectivemem data counter, which is
supported only for backward compatibility.
n
Counter: totalmb
n
Stats Type: Absolute
n
Unit: Megabytes (MB)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
Chart Analysis
Memory usage is not an indicator of performance problems. Memory can be high if a host is swapping or
ballooning, which can result in virtual machine guest swapping. In such cases, check for other problems,
such as CPU over-commitment or storage latencies.
If you have constantly high memory usage in a cluster, resource pool, or vApp, consider taking the
following actions.
Table 1‑14. Memory Performance Enhancement Advice
# Resolution
1 Verify that VMware Tools is installed on each virtual machine.
2 Verify that the balloon driver is enabled. The balloon driver is installed with VMware Tools and is critical to
performance. 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. 19