Multiprocessing

What Does the fork() System Call Do?

fork() creates a new process by duplicating the calling process almost exactly, returning twice — once in the parent with the child’s process ID, and once in t…

What is Cache Coherence in Multiprocessor Systems?

Cache coherence is the guarantee that all CPU cores in a multiprocessor system see a single, consistent view of a shared memory location, even though each core…

What Hardware Support Exists for Process Synchronization?

Hardware support for process synchronization refers to CPU instructions — such as Test-and-Set, Swap (Exchange), and Compare-and-Swap — that execute as a singl…

What is Load Balancing in a Multiprocessor OS?

Load balancing in a multiprocessor OS is the scheduler policy of spreading runnable tasks evenly across all available CPU cores so no core sits idle while anot…

Symmetric vs Asymmetric Multiprocessing (SMP vs AMP)

Symmetric multiprocessing (SMP) has every CPU core run the same copy of the OS kernel and share equal access to memory and I/O, while asymmetric multiprocessin…

What is NUMA Architecture?

NUMA (Non-Uniform Memory Access) is a multiprocessor memory architecture where each CPU (or group of cores) has its own local memory bank that it accesses quic…

What is Processor Affinity?

Processor affinity is the tendency, or explicit configuration, for a process or thread to keep running on the same CPU core it ran on before, so it can keep re…