Fixed Priority Pre-emptive Scheduling
The OS assigns a fixed priority rank to every process, and the scheduler arranges the processes in the ready queue in order of their priority. Lower priority processes get interrupted by incoming higher priority processes.
- Overhead is not minimal, nor is it significant.
- FPPS has no particular advantage in terms of throughput over FIFO scheduling.
- Waiting time and response time depend on the priority of the process. Higher priority processes have smaller waiting and response times.
- Deadlines can be met by giving processes with deadlines a higher priority.
- Starvation of lower priority processes is possible with large amounts of high priority processes queuing for CPU time.
Famous quotes containing the words fixed and/or priority:
“I was not at all shocked with this execution at the time. John died seemingly without much pain. He was effectually hanged, the rope having fixed upon his neck very firmly, and he was allowed to hang near three quarters of an hour; so that any attempt to recover him would have been in vain. I comforted myself in thinking that by giving up the scheme I had avoided much anxiety and uneasiness.”
—James Boswell (17401795)
“Weekend planning is a prime time to apply the Deathbed Priority Test: On your deathbed, will you wish youd spent more prime weekend hours grocery shopping or walking in the woods with your kids?”
—Louise Lague (20th century)