The emulation of the virtual network I/O card is based on the
Intel I8254X family. Thus, the virtual network card (vNIC) is presented
to the guest operating system as PCI-X 1000Base-T with the speed of
1 Gb regardless of the physical network interface card backing the
vswitch. This emulation could lead to an incorrect calculation of
vNIC performance by some network performance applications on the guest.
For example, on a Windows guests, the Task Manager —> Network
Performance display shows 1 Gb utilization. All calculations on the
Windows utilization are then based upon this value rather than the
speed of the backing device on the VM Host.
To accurately calculate vNIC performance, take into consideration
the speed of the backing device on the Integrity VM Host.
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