Hi Guys,

We're undertaking some performance benchmarking as part of a proposed upgrade from 4.1U3 to 5.5U1, and running identical VMs (Red Hat 5.5, 2x vCPU, 4086 RAM, Up to date Tools and vHW) on identical hosts (Dell M610 8x 2.9GHz CPU / 32GB RAM) we see some notable differences when comparing esxtop outpu for VM CPU statistics.

For example - at idle, ESXi 5.5 is running nearly 500 worlds, whereas 4.1 is running 190.

At the VM level, when they are running our test application, we see the following significant differences:

4.1

“NWLD” = 5 per VM

“%WAIT” = 480 per VM

“%RDY” = 0.05 per VM

“TIMER/s (Interrupts)” = 3003 per VM

EMIN = ~7300 per VM

5.5

“NWLD” = 8 per VM

“%WAIT” = 780 per VM

“%RDY = 3.0 per VM

“TIMER/s (Interrupts)” = 1001 per VM

“EMIN” = ~6200 per VM

The knock on effect is that we are losing UDP packets, but that's another SR entirely!

Thanks for your time,

Dan