6.5.1

Table Of Contents
Table 112. Disk I/O Performance Enhancement Advice (Continued)
# Resolution
8 For resource-intensive virtual machines, separate the virtual machine's physical disk drive from the drive with the
system page le. It alleviates disk spindle contention during periods of high use.
9
On systems with sizable RAM, disable memory trimming by adding the line MemTrimRate=0 to the virtual
machine's VMX le.
10 If the combined disk I/O is higher than a single HBA capacity, use multipathing or multiple links.
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 113. 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-specic 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)
N The totalmb data counter is the same as the eectivemem 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.
Chapter 1 Monitoring Inventory Objects with Performance Charts
VMware, Inc. 17