Q9Computer Architecture
Question
Q.9. What do you mean by memory management unit?
Answer
A Memory Management Unit (MMU) is a hardware component that translates virtual addresses generated by the CPU into physical memory addresses, and enforces memory protection/access permissions, enabling virtual memory and multi-process memory isolation.
A Memory Management Unit (MMU) is a hardware component, typically integrated within the CPU, responsible for translating the virtual (logical) memory addresses generated by running programs into the actual physical memory addresses used to access RAM, using page tables (or segment tables) maintained by the operating system; the MMU additionally enforces memory access permissions and protection boundaries between different processes (preventing one process from directly accessing another process's memory), and signals a page fault to the operating system whenever a program accesses a virtual address whose corresponding data is not currently present in physical memory, triggering the OS to load the required data from secondary storage — the MMU is the essential hardware component that makes virtual memory and multi-process memory protection practically feasible at the speed required for normal program execution.