Everything about VMware

Slow SSD perfomance with ESXi 6.5 and older AHCI controllers

ESXi 6.5 includes a new native driver (vmw_ahci) for SATA AHCI controllers, but that introduces performance problems with a lot of controllers and/or disks.

Try to disable the native driver and revert to the older sata-ahci driver by running

 esxcli system module set --enabled=false --module=vmw_ahci

Reboot the server after changing it and your performance should be OK again.

Determine the NIC firmware and driver version for ESXi 5.5

In ESXi 5.1 you could use the command ethtool -i vmnicX to get the firmware and driver version for the Network interface card. In 5.5 you get an error: Can not get control fd: No such file or directory.

 

To get the firmware and driver version use the following command in 5.5:

esxcli network nic get -n vmnicX

To get a list of nics:

esxcli network nic list