Providing predictable scheduling of programs using repeating precomputed schedules on discretely scheduled and/or multiprocessor operating systems

A method for a computer system having a plurality of processors comprising:

• a) receiving a constraint for a thread in an activity specifying a desired earliest start time, amount of requested execution time, and a deadline;
• b) determining the thread has previously been run on a particular processor;
• c) upon determining that the thread has previously been run on a particular processor,
• i) determining whether the constraint can be scheduled on the particular processor;
• ii) upon determining that the constraint can be scheduled on the particular processor, scheduling the constraint on the particular processor;
• iii) otherwise, scheduling the constraint on a different processor;
• and,
• d) otherwise, scheduling the constraint on a different processor.

A method for a computer system having a plurality of processors comprising:

• a) receiving a reservation for an activity that previously had no reservations, the reservation specifying a recurring desired number of time units within a desired period;
• b) determining whether a thread within the activity has previously been run on a particular processor;
• c) upon determining that the thread has previously been on a particular processor,
• i) determining whether the reservation can be scheduled on the particular processor;
• ii) upon determining that the reservation can be scheduled on the particular processor, scheduling the reservation on the particular processor;
• iii) otherwise, scheduling the reservation on a different processor;
• and,
• d) otherwise, scheduling the reservation on a different processor.