Fixed Allocation

Fixed allocation is a memory management technique where a fixed amount of memory is pre-allocated to a process or system component at startup or design time, and this allocation does not change during runtime. It is commonly used in embedded systems, real-time applications, and operating systems to ensure predictable performance and avoid fragmentation. This approach contrasts with dynamic allocation, where memory is allocated and deallocated as needed.

Also known as: Static Allocation, Pre-allocation, Fixed Memory Allocation, Static Memory Management, Pre-allocated Memory

Why learn Fixed Allocation?

Developers should learn fixed allocation when working on systems with strict resource constraints, such as embedded devices, real-time operating systems (RTOS), or safety-critical applications where deterministic behavior is essential. It is particularly useful for avoiding memory fragmentation, reducing overhead from dynamic allocation, and ensuring that critical tasks always have the memory they need without runtime delays.

Learning Resources

• docs: Memory Management: Fixed vs. Dynamic Allocation
• tutorial: Embedded Systems Memory Management Tutorial
• docs: Real-Time Operating Systems and Fixed Allocation
• tutorial: C Programming: Static vs Dynamic Memory
• video: Memory Allocation in Operating Systems - Video