Back to glossary

L1 Cache

The primary cache, which is the fastest and smallest level of cache memory in a computer's hierarchy.

Categoryhardware

Overview

L1 (Level 1) cache is built directly into the CPU core. It is designed to be as fast as the processor itself, providing data with almost zero latency.

Structure

L1 cache is typically split into two parts:

  • L1i (Instruction Cache): Stores the instructions the CPU needs to execute.
  • L1d (Data Cache): Stores the data the CPU is currently working on.

Size

Usually very small, ranging from 32KB to 128KB per core in modern processors.

Related Terms

Cache MemoryL2 CacheCentral Processing Unit