What are some of the problems the operating system scheduler has to solve? i with mainframes, the scheduler has to decide whether a batch job or an interactive user at a terminal should go next, and manage scarce CPU resource ii with personal computers, which run many programs at the same time, the scheduler needs to manage the scarce CPU with a more clever and efficient algorithm iii a key issue related to scheduling is when to make scheduling decisions, for example: when a process creates a new process should we run the parent or the child next, when a process blocks waiting on I/O, another process has to be selected to run, and so on iv giving each process a fair share of the CPU O i and ii O i, ii, and iv ii andiv