Hyper-v takes a long time to create snapshots

I'm not sure when, but I've noticed as of recently, whenever I go to make a snapshot of certain machines, it hangs at 2% for a good while and then eventually finishes (fairly quickly, actually). I don't believe I noticed it before. Is it waiting for something else to finish?

I've also noticed that sometimes during a reboot of the guest machine, it takes an equal amount of time to stop the guest before rebooting.

I've already rebooted the host. I'm running Windows server 2012. Thanks.