While looking into Windows IO/Mem performance on a rainy day (i.e. “no golf”), I noticed something that I do in my Hyper-V lab setup that kills performance.
I build new VMs all of the time. Usually they are for a simple test I build with MDT and I throw away the VM after a couple of weeks. I do it so often I don’t really think about it much.
Well when I looked at the performance of the server, I noticed that when I start up a VM, it remembers the virtual CD I used to build it. So parts of the virtual iso file end up getting loaded into memory.
So duh! Got to remember to unmount the iso. Especially on the ones I keep with the snapshots.