查看本機的 Interface

esxcfg-nics -l

Name    PCI           Driver      Link Speed     Duplex MAC Address       MTU    Description
vmnic0  0000:02:00.00 r8168       Up   100Mbps   Full   90:2b:34:98:0f:6f 1500   Realtek Realtek 8168 Gigabit Ethernet
vmnic1  0000:03:02.00 tg3         Down 0Mbps     Half   00:10:18:1c:aa:5e 1500   Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet

Enhanced vmxnet:

The paravirtualized driver shares a ring buffer between the virtual machine and the vmkernel, supports transmission and interrupt coalescing and offloads TCP checksum calculations to the physical cards. These optimizations improve performance by reducing CPU cycles on the host and resident VMs.

The vmxnet 3 adapter is the latest generation and was designed with performance in mind. In addition to the optimizations mentioned previously, it also provides multi-queue support and IPv6 offloads. Configuring the vmxnet 3 adapter requires at least hardware version 7 and a supported OS.

Hardware TCP Segmentation Offloading (TSO4, TSO6)
Hardware Large Receive Offloading (LRO) <-- (VMXNET2 and VMXNET3 virtual machine adapters)

TSO

Host 的 TSO 設定

# On ESX/ESXi 4.x hosts:
esxcfg-advcfg -g /Net/UseHwTSO
esxcfg-advcfg -s 1 /Net/UseHwTSO

On ESXi 5.0 hosts and later:
esxcli system settings advanced list -o /Net/UseHwTSO
esxcli system settings advanced set -o /Net/UseHwTSO -i 1

#  physical NIC 對 TSO 的支援

ethtool -k vmnic0
Offload parameters for vmnic0:
Cannot get device udp large send offload settings: Function not implemented
Cannot get device generic segmentation offload settings: Function not implemented
rx-checksumming: off
tx-checksumming: off
scatter-gather: off
tcp segmentation offload: off
udp fragmentation offload: off
generic segmentation offload: off

ethtool -K vmnic0 tso on

Cannot set device tcp segmentation offload settings: Function not implemented

/etc/rc.local.d/local.sh

# Linux guest

ethtool -K ethY tso on

LRO

Hardware LRO is active for VMXNET2 and VMXNET3 virtual machine adapters by default.

# To enable or disable hardware LRO on the physical NIC for VMXNET2 and VMXNET3 adapters

On ESX/ESXi 4.x hosts:
esxcfg-advcfg -s 1 /Net/Vmxnet3HwLRO

On ESXi 5.0 hosts and later:
esxcli system settings advanced set -o /Net/Vmxnet3HwLRO -i 1

LRO is enabled on the host

On ESX/ESXi 4.x hosts:
esxcfg-advcfg -g /Net/Vmxnet2HwLRO
esxcfg-advcfg -g /Net/Vmxnet3HwLRO

On ESXi 5.0 hosts and later:
esxcli system settings advanced list -o /Net/Vmxnet2HwLRO
esxcli system settings advanced list -o /Net/Vmxnet3HwLRO

Linux guest:

# VMXNET3

To enable LRO:
ethtool -K ethY lro on

# VMXNET2

modprobe vmxnet3 disable_lro=0
modprobe vmxnet disable_lro=0

DOC

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd...