procesrammer

Procesrammer are fixed-size blocks of physical memory used by a computer’s virtual memory system to store the active pages of processes. In paging-based memory management, physical memory is divided into an array of frames; each frame can hold one page of a process’s virtual address space. The number of frames and their contents are managed by the operating system and hardware.

A frame table tracks each frame’s status and ownership; the translation from a process’s virtual page to a frame is done via the page table, with the frame number used to access memory. The memory management unit (MMU) and, in many systems, a translation lookaside buffer (TLB) accelerate this address translation, providing fast access to the correct physical location.

Allocation and replacement are core responsibilities of the memory manager. When a process needs a page that is not in memory, a page fault occurs. The OS selects a free frame or evicts a page from a currently used frame to secondary storage, then loads the required page into the frame and updates the relevant tables. Replacement algorithms (e.g., FIFO, LRU, CLOCK) determine which frame to free.

Sizes and considerations vary by system. Frame sizes are typically fixed; common sizes include 4 KB, though larger sizes known as huge pages may also be supported. Larger frames reduce page-table overhead but can increase internal fragmentation and waste, while smaller frames improve granularity but raise management overhead. Pages can be shared between processes (e.g., read-only shared libraries) or duplicated via copy-on-write.

Significance: procesrammer are central to virtual memory, enabling isolation, on-demand loading, and efficient use of physical memory. They reflect a collaboration between hardware support (MMU, TLB) and software (kernel memory management) in modern operating systems.