daveysc's version from 2015-07-22 14:59
CPU CacheCPU cache is a kind of static RAM (SRAM) that is used to temporarily store important data. It is similar to the RAM installed on the motherboard in that it is used to store data to be accessed by the CPU and that it is volatile (requires power to retain data). This memory is accessed before the motherboard RAM.
There are 3 levels of cache in modern CPUs:
Level 1 (L1) cache is located on the die (physical core). This is the fastest but also has the least storage.
Level 2 (L2) cache is located off of the die, but is dedicated to a single core. This is slower but has a higher capacity than L1 cache.
Level 3 (L3) cache is located further off of the die than L2 cache and is shared between all of the cores. This is slower than both the L1 and L2 caches but has the most storage. Older PC processors may not have this.
Note: Cache is pronounced like "cash," not "cash-ay."
|Level 1 (L1) Cache||Located on the die. Fastest and smallest.|
|Level 2 (L2) Cache||Located off of the die, but still dedicated to a single physical core. Slower but slightly higher capacity.|
|Level 3 (L3) Cache||Located farthest from the die and is shared between all off the physical cores. Slowest but has the highest capacity.|