Usage of all VM's across hosts?

Hi all,

I have been requested by our CIO to gather information regarding our cluster. We have currently have 5 servers and 181 VM's running across them, but we are starting to run low on memory.

Is there anyway to generate a usage report to see which VM's are rarely or, if ever, used? I know you can look at each VM, but I would like a "totals" type of report if possible. I can then justify shutting some of them down as they are never used and are just consuming resources.

We are running ESXi 6.0.0

Many thanks.