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Table Of Contents
Table 1116. 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 the 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.
Network (Mbps)
The Network (Mbps) chart displays network bandwidth for the virtual machine.
This chart is located in the Home view of the Virtual Machine Performance tab.
Table 1117. Virtual Machine Counters
Chart Label Description
Usage Average rate at which data is transmitted and received across all virtual NIC instances
connected to the virtual machine.
n
Counter: usage
n
Stats Type: Rate
n
Unit: Megabits per second (Mbps)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
Chart Analysis
Network performance depends on the application workload and network configuration. Dropped network
packets indicate a bottleneck in the network. To determine whether packets are being dropped, use
esxtop or the advanced performance charts to examine the droppedTx and droppedRx network counter
values.
If packets are being dropped, adjust the virtual machine shares. If packets are not being dropped, check
the size of the network packets and the data receive and transfer rates. In general, the larger the network
packets, the faster the network speed. When the packet size is large, fewer packets are transferred,
which reduces the amount of CPU required to process the data. When network packets are small, more
packets are transferred but the network speed is slower because more CPU is required to process the
data.
Note In some instances, large packets might result in a high network latency. To check the network
latency, use the VMware AppSpeed performance monitoring application or a third-party application.
vSphere Monitoring and Performance
VMware, Inc. 93