VMWare Fusion consistently having performance problems for me of late. I've cursed their name and thought ah well I will switch to Virtual Box or Parallels some time in the future. Just today it occurred to me that the default VM storage directory is within /User/Username home directory!
Why is that significant? I have (like many Mac wielding infosec folk) FileVault home folder encryption enabled, this combined with the option to encrypt swap memory enables obviously cripples the performance of resource intensive Virtualization.
The simple solution is to relocate the VM directories out of your home directory for example:
#mv /User/Username/Documents/Virtual\ Machines.localized/ /vmware
#chown -R username:staff /vmware
*** Update *** this more than quadruples the speed of your VM's if you have filevault on.