I recently got a nice new iMac. I installed Parallels on it and created a couple of virtual machines. I keep running into major slowdowns in performance where my mouse barely moves. It appears to be due to memory pressure. Is 16 GB not enough to run 2 virtual machines at the same time in Parallels? Is this normal memory usage?
You haven't said the most important bit of info, how much RAM is assigned to each VM? I see from the process list, the Win 8.1 has at least 8 GB assigned to it. You should consider that OS X Yosemite, the Host, works well with more than 4 GB, so the sum of the assigned RAM to both VMs shouldn't exceed 12 GB (6 each for instance). I also see you are running Chrome (with lots of tabs open), and Spotify among others on the OS X side, this will increase the memory pressure, Chrome can easily consume GBs of RAM. So this decreases the amount available for the VMs. I would recommend that the sum of both VMs' RAM should be 10 GB for this usage scenario.
