cps 590 chapt 7

Memory Management

The process of dynamically dividing up main memory to accommodate multiple processes in a multiprogramming system.

Relocation

The ability to move a process to a different area of memory when it is swapped back in.

Protection

Ensures that processes are isolated from each other, preventing interference.

Sharing

Multiple processes can access the same portion of memory.

Logical Organization

Programs are organized into modules, allowing independent compilation and different protection levels.

Physical Organization

Managing the flow of information between main memory and secondary memory.

Fixed Partitioning

Memory is divided into fixed-size partitions for processes.

Dynamic Partitioning

Memory is allocated in variable-size partitions based on process needs.

First-Fit Algorithm

Allocate the first available block that is large enough.

Best-Fit Algorithm

Allocate the smallest block that is large enough.

Next-Fit Algorithm

Allocate the next available block after the last allocation.

Buddy System

A memory allocation system that divides memory into blocks of size 2^k.

Paging

Memory management scheme that eliminates external fragmentation by dividing memory into fixed-size frames.

Page Table

A data structure that maps logical page numbers to physical frame numbers.

Segmentation

Memory is divided into variable-size segments based on logical divisions.

Logical Address

A reference to a memory location independent of current data assignment.

Physical Address

The actual location in main memory.

Internal Fragmentation

Wasted space within a partition or page because the allocated block is larger than the data it holds.

External Fragmentation

Wasted space between partitions or segments due to the allocation and deallocation of variable-size blocks.

Compaction

The process of shifting processes to consolidate free memory.

Virtual Memory

A memory management technique that allows processes to use more memory than physically available.

Overlays

A technique where parts of a program are loaded into memory only when needed.

Base Register

Holds the starting address of a process in memory.

Bounds Register

Holds the ending address of a process.

Page Size Power of 2

Page size is typically a power of 2 to simplify address translation.