Heterogeneous (big/little) cores
Beginner
A chip with two kinds of cores: big fast ones for urgent work and small thrifty ones for background work.
Novice
A multicore design mixing core types that run the same instructions but sit at different speed and power points. The operating system places each task on a core that fits it. Arm calls the approach big.LITTLE; Intel calls its two kinds P-cores and E-cores.
Expert
Single-ISA asymmetry: big out-of-order cores for latency-critical or serial phases, small cores for throughput per watt and per mm². Needs capacity- and energy-aware scheduling and ISA parity across core types, including vector width.
Explained in Multicore and vector units (Architectures).
See also: Multicore processor, Amdahl’s law.