Page Fault
A page fault is a type of exception raised by computer hardware when a running program accesses a memory page that is not currently mapped into the virtual address space by the memory management unit (MMU). It occurs in systems that use virtual memory, indicating that the required data is not in physical RAM and must be loaded from secondary storage like a hard disk or SSD. This mechanism allows operating systems to efficiently manage memory by swapping pages between RAM and disk as needed.
Developers should understand page faults to optimize application performance, especially in memory-intensive systems like databases, game engines, or high-performance computing. Knowledge of page faults helps in debugging memory-related issues, reducing latency by minimizing unnecessary disk I/O, and designing efficient algorithms that consider memory locality. It's crucial for system programming, operating system development, and performance tuning in environments with limited physical memory.