Virtualization
New to this. Is it possible to run El Capitan for some applications and Catalina for the rest by using virtualization?
MacBook
Question marked as
Don't even consider this on a MacBook, or MacBook Pro with less than 16GB RAM, and sufficient, and fast internal, or external SSD storage. Catalina will want at least 4GB to just run, Parallel's will want around 1 - 2 GB of RAM to run the guest operating system, and the latter will want at least 4GB RAM (or more for applications you intend to run there).
I am running El Capitan as a Parallel's guest on a 2013 27 in Imac (Mojave 10.14.6) with a quad core i5. It has 24 GB RAM, and the Parallel's guest is stored on an external 512 GB Crucial SSD via USB 3.0. I allocated 8GB RAM to El Capitan. It has acceptable performance.
