I am currently trying to run some calculations on material studios, and I noticed that allocating fewer cores makes the calculations take longer than when more cores are allocated. I have a total of 68 different calculations to run. Hence I am curious: what would be more time efficient? Would allocating 19 of my PC's cores to run my calculations one at a time work out faster than allocating my cores in the order of 6,6, and 7 to run 3 calculations simultaneously?

The conventional thinking is multi-tasking is always faster, but I am unsure if the same stands true with PC cores and calculations.

I would greatly appreciate any assistance.