Which frame allocation strategy allocates physical memory frames to processes strictly proportional to their logical size?
Option A is correct. Proportional Allocation distributes available frames based on relative size: $a_{i} = (s_{i} / S) \cdot m$, where $s_{i}$ is process size and S is total size.
What happens to system performance when the Degree of Multiprogramming is increased beyond optimal limits without sufficient RAM?
Option C is correct. Beyond a threshold, adding more processes causes each to get fewer frames, sparking constant page faults and thrashing, causing CPU utilization to plummet.
In Demand Paging, what is 'Lazy Swapper' (or Pager)?
Option A is correct. A pager brings a page into memory only when needed (on-demand), avoiding pre-swapping unneeded pages.
Which data structure implementation can be used to track page recency for LRU page replacement?
Option A is correct. LRU can be implemented with a stack (doubly linked list): whenever a page is referenced, it is moved to the top; the bottom page is evicted.
What is the main function of the Page-Fault Frequency (PFF) strategy in OS?
Option B is correct. PFF establishes acceptable page-fault rate bounds. If page-fault rate exceeds upper bound, allocate more frames; if below lower bound, remove frames.