in reply to
Efficient way to fork processes and keep a running count?
As per the scenarios you showed, IMHO, there is no need to fork a fourth child, the second child can do the read of disc4 once it is done with disc2.
As only 3 drives exist, 3 processes at a time would be sufficient, that too reusing the existing pool of processes without forking a new one is a good idea.
Forking more number of processes would increase unnecessary complexity.
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