CPUMikroarchitekturkompatibilität

CPUMikroarchitektur, often shortened to CPU microarchitecture, refers to the specific implementation of an instruction set architecture (ISA) in a central processing unit (CPU). While the ISA defines the set of instructions a processor can understand and execute, the microarchitecture dictates how those instructions are physically processed. This includes the design of the internal components such as the arithmetic logic unit (ALU), control unit, registers, and the pipeline stages. Different microarchitectures can implement the same ISA but achieve varying levels of performance, power efficiency, and feature sets.

Key aspects of microarchitecture design involve optimizing instruction fetching, decoding, execution, and retirement. Techniques like pipelining, out-of-order execution, branch prediction, and caching are all part of microarchitectural innovation. Pipelining allows multiple instructions to be in different stages of execution simultaneously, increasing throughput. Out-of-order execution reorders instructions to keep execution units busy, even if data dependencies would normally cause stalls. Branch prediction attempts to guess the outcome of conditional branches to avoid pipeline flushes. Caching stores frequently accessed data closer to the CPU core for faster retrieval.

Major CPU manufacturers like Intel and AMD continuously develop new microarchitectures for their processors. For example, Intel's Core series has seen numerous microarchitectural advancements over generations, each with a codename like "Skylake" or "Alder Lake," while AMD has progressed through architectures like "Zen" and "Zen 2." Each new microarchitecture aims to improve performance per clock cycle (IPC), reduce power consumption, and integrate new capabilities, all while adhering to established ISAs like x86-64. Understanding microarchitecture is crucial for comprehending the performance differences between various CPU models and generations.