VMware

txqueuelen

Tuned on the ESXi hosts.

Purpose: Default value of 500 is too small. The recommendation is to set to 10000 which increases the network throughput of a VM.ESXi defaults the value to 500 and permits a max value of 10000.

Log in to the CLI console of the ESX host and run the below esxcli command:

# esxcli system settings advanced set -i=10000 -o=/Net/MaxNetifTxQueueLen

Increase Ring Buffer on the Physical Ethernet interfaces

Tuned on the ESXi hosts.

Purpose: Improves the overall network throughput of the host. On an ESXi host Rx buffer defaults to 512 and Tx buffer defaults to 1024 and the max value for both is 4096.

Log in to the CLi console of the ESX host and run the below esxcli commands:

# esxcfg-nics -l (lists all the physical NICs attached to the host)
# ethtool -g <interface name> (shows the current ring buffer size)
# ethtool -G <interface name> rx 4096  (increases the rx buffer size to 4096)
# ethtool -G <interface name> tx 4096  (increases the tx buffer size to 4096)

Multiqueue

Already enabled on ESXi for vmxnet3 adapters.

Purpose: Improves the network throughput of a VM.

Advanced NUMA settings

Tuned on ESXi hosts.

Purpose: Prevents the ESXi scheduler to move VMs around from one NUMA node to another.

Log in to the CLI console of the ESX host and run the below esxcli commands:

# esxcli system settings advanced set -i=0 -o=/Numa/SwapLoadEnable
# esxcli system settings advanced set -i=0 -o=/Numa/SwapLocalityEnable