Tue Jul 05, 2011 9:39 pm
My tips for performance on vmware:
ESX(i)
Use ESX/ESXi instead of Server/Workstation.
e1000
Make sure the virtual machine gets Intel (e1000) virtual ethernet instead of AMD (vlance).
They say the trick is setting the guest to a 64 bit type. You can also manually do a ethernet0.virtualDev = "e1000"
Else you'll see a lot of "dropped" packets in Interfaces, and packet loss on simple things like pings.
Queue sizes
If you use queue trees make sure the queue types are big enough.
Else you'll see a lot of "dropped" packets in Queue Tree (if you enable "Dropped" colum) for queues that are not saturated, and packet loss on simple things like pings.
Rx buffers
If you use queuing at all and have more than 150Mb per interface you may also experiment silent packet drops (like in pings). This is happening at the vmware's vSwitch level, and you can check it with the "esxtop" tool (column DRPRX).
The solution to this is increasing the RX buffer of the (virtual) ethernet card with ethtool or modprobe parameters. Unfortunately there is no nice way to do this.
I have experimentally edited the binary driver and changed default value from 256 to 2048 and got it ok by now with at least 300Mb.