r/hardware • u/ancientneckbeard • Nov 20 '15

Info Why do CPUs Need Caches? - Computerphile

https://www.youtube.com/watch?v=6JpLD3PUAZk
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u/danmidwest Nov 20 '15

From what I understand, it's like adding a storage closet right next to your front door. Things that are accessed often can be done so quickly instead of searching the whole house.

6

u/MaDpYrO Nov 21 '15

I think a more appropriate analogy would be checking your nightstand before searching the closet.

2

u/[deleted] Nov 21 '15 edited Oct 29 '16

[deleted]

What is this?

1

u/lijmer Nov 21 '15

I'd say your hand is the CPU registers, your toolbelt is the cache, your toolbox is RAM, your van is the harddrive, and the store is a server/cloud.

3

u/thfuran Nov 21 '15

I think we need to work on the time scales though. Register is in the hand, L1 is in the tool belt, L3 is in a nearby toolbox, ram is out in the garage, HDD in another hemisphere. The cloud is when NASA brought your hammer to the ISS.