Latency

Latency. Latency. You hear about this every day. Understanding latency is essential in all parts of our systems, including registers, main memory, disk, and network. In addition, understanding these latencies is vital so you can reason about various aspects of your system.

Latency is physically a consequence of the limited velocity at which any physical interaction can propagate, which is always < speed of light.

Latency always tends to sneak up on you. Oh, 1ms per item processing isn't bad. What if I had to process a billion items? That's just over 11 days. 🤯