Explain why implementing synchronization primitives by disabling interrupts is not appropriate in a single-processor system if the synchronization primitives are to be used in user-level programs?

Answer 1

Interrupts are not sufficient in multiprocessor systems since disabling inter rupts only

prevents other processes from executing on the processor in which inter rupts were disabled; there are

no limitations on what processes could be executing on other processors and therefore the process

disabling interrupts cannot guarantee mutually exclusive access to program state.

Answer 2

If a user-level program is given the ability to disable interrupts, then it can disable the timer interrupt and prevent context switching from taking place, thereby allowing it to monopolize the processor so the other process may never execute so there will be starvation.

Answer 3

If a user-level program is given the ability to disable interrupts, then it can disable the timer interrupt and prevent context switching from taking place, thereby allowing it to use the processor without letting

other processes to execute.

Explain why interrupts are not appropriate for implementing synchronization

primitives in multiprocessor systems.

Interrupts are not sufficient in multiprocessor systems since disabling interrupts only prevents other processes from executing on the processor in which interrupts were disabled; there are no limitations on what processes could be executing on other processors and therefore the process disabling interrupts cannot guarantee mutually exclusive access to program state.