# Latency Numbers Every Developer Should Know
AI-readable version of this post.
Path: /systems/latency-numbers-every-dev-should-know
Category: Systems
Date: 2019-08-12
Author: Performance
Reading time: 1 min
Description: Practical intuition for network and storage costs.
## Why this matters

Most architecture mistakes come from bad latency intuition.

## Typical hierarchy

- CPU cache: nanoseconds
- RAM: tens to hundreds of nanoseconds
- SSD: microseconds to milliseconds
- Network: milliseconds

## Design implication

Batch round trips and avoid synchronous chatty boundaries.