Will the cumulative HDD read/write speed change when multiple processes are running?

Question

Iron

Good evening.
Not a practical question, just curious. Suppose there is an HDD, and something is being copied from partition A to partition D. Obviously, everything is simple here: the heads find the necessary blocks and write them to the specified location, all this is flavored with temporary data caching technologies in memory.
But what if there are several copying processes, and all of them - with different file packages and from different sections \ are physically located on different pancakes? How will the disk behave in this case? Will it "rush around", satisfying the needs of each of the processes in turn (in this case, the total speed will decrease due to the cost of constantly moving heads for nothing), or the controller \ OS optimizes everything so that reading and writing occur constantly, with minimal loss of efficiency (in this case, the cumulative speed will either not change or will decrease slightly)?
Thanks in advance.

Answer 1

It will batch rush across the disk. The speed naturally decreases.