6.0.1

Table 1‑105. Data Counters
Chart Label Description
Read Requests Number of virtual disk read commands completed on each virtual disk on
the virtual machine. The aggregate number of all virtual disk read
commands per second is also displayed in the chart. Read rate = blocksRead
per second × blockSize
n
Counter: read
n
Stats Type: Rate
n
Unit: KiloBytes per second (KBps)
n
Rollup Type: Average
n
Collection Level: 3
Write Requests Number of virtual disk write commands completed on each virtual disk on
the virtual machine per second. The aggregate number of all virtual disk
write commands per second is also displayed in the chart. Write rate =
blocksWritten per second × blockSize
n
Counter: write
n
Stats Type: Rate
n
Unit: KiloBytes per second (KBps)
n
Rollup Type: Average
n
Collection Level: 3
Memory (%)
The Memory (%) chart monitors virtual machine memory usage.
This chart is located in the Home view of the virtual machine Performance tab.
Virtual Machine Counters
NOTE Guest physical memory refers to the virtual hardware memory presented to a virtual machine for its
guest operating system.
Table 1‑106. Data Counters
Chart Label Description
Usage Amount of guest physical memory currently in use on the virtual machine.
n
Counter: usage
n
Stats Type: Absolute
n
Unit: Percentage (%)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
Chart Analysis
A virtual machine's memory size must be slightly larger than the average guest memory usage. This enables
the host to accommodate workload spikes without swapping memory among guests. Increasing the virtual
machine memory size results in more overhead memory usage.
If sufficient swap space is available, a high balloon value does not cause performance problems. However, if
the swapin and swapout values for the host are large, the host is probably lacking the amount of memory
required to meet the demand.
If a virtual machine 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 meet the memory requirements. This
leads to memory reclamation, which might degrade performance. If the active memory size is the same as
the granted memory size, demand for memory is greater than the memory resources available. If the active
memory is consistently low, the memory size might be too large.
vSphere Monitoring and Performance
76 VMware, Inc.