Multiprogramming involves running multiple Programs on a single CPU to maximize CPU utilization
Goldilocks Multiprogramming
More multiprogramming does not equal more better.
Too many Processes will result in Thrashing and constant Page Faults
- Overcommitment of memory (Thrashing)
- Bigger Working Set than physical memory can hold
- System becomes I/O bound, with thrashing’s Swap Space spamming and page fault constant Traps
Memory Pressure
Memory Pressure
How many page references are there in physical memory?
where
gives the Working Set Size of an ith Process where is the number of processes running working set set is exactly the count of page references per process If
then swap out some processes If then increase degree of Multiprogramming This is a concern of the Medium Term Scheduler
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