Operating System MCQs

A TLB stores recent virtual-page to physical-frame translations close to the processor.
It reduces the need to access the page table in main memory for every reference.

On a TLB hit, the processor obtains the frame number without an additional page-table memory access.
This lowers effective memory-access time.

The page number selects a page-table entry, and the offset selects a byte within that page.
The physical address combines the resulting frame number with the unchanged offset.

A power-of-two page size lets hardware divide an address by selecting high and low bit ranges.
No arithmetic division is needed to identify the page number and offset.

Paging can place pages in any free frames, so one large contiguous physical hole is unnecessary.
Some internal fragmentation may still occur in the final page of a process.

Compaction relocates processes so separated free areas become one larger hole.
It requires dynamic relocation support and can be expensive.

The buddy system organizes blocks by powers of two for fast splitting and coalescing.
Two free buddies of the same size can merge into their parent block.

Paging divides logical memory into equal-sized pages.
Pages can be placed into any available physical frames.

Physical memory is divided into frames of the same size as logical pages.
The page table records which frame contains each page.

A page table provides the translation information required for paged address spaces.
Each process normally has its own mapping because its virtual address space is independent.

Single-partition allocation supports only one resident user process in the available user-memory region.
It is simple but provides poor multiprogramming and memory utilization.

Fixed partitions have predetermined boundaries and sizes established before process placement.
A process must fit in one available partition, which can cause internal fragmentation.