I have a relatively new iMac with plenty of memory and a fusion drive, and I have done all the things in the Help screens that are supposed to make your VMs run faster. But today I play around with hardware, and discovered this: If you are blessed with a Mac with an SSD, you already know this, but by using a moderately fast USB3 external SSD I have experienced a wonderful briskness to the operation of my Windows 10 VM under Parallels 16. If you have access to an SSD, give it a try. You'l be delighted!
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