Os Memory Management Questions
The buddy system is a memory allocation technique used in operating systems to manage memory efficiently. It involves dividing the available memory into fixed-size blocks, known as buddies, which are powers of two. Each buddy represents a specific range of memory addresses.
When a memory request is made, the system searches for the smallest buddy that can satisfy the request. If the buddy is larger than needed, it is split into two equal-sized buddies. One buddy is allocated to the request, while the other remains available for future allocations. This splitting process continues until the smallest buddy that can fulfill the request is found.
When memory is deallocated, the system checks if the buddy's adjacent buddy is also free. If so, the buddies are merged back together to form a larger buddy. This merging process continues until no adjacent buddies are free.
The buddy system ensures that memory is allocated and deallocated in a way that minimizes fragmentation. It allows for efficient allocation of memory blocks of varying sizes, as the splitting and merging operations maintain a balance between large and small buddies. Additionally, the buddy system provides fast allocation and deallocation times, as the search for an appropriate buddy is relatively quick.
Overall, the buddy system is a practical and efficient approach to memory allocation, particularly in systems where memory needs to be managed dynamically.