Exactly. At an investment bank for which I used to work in NYC, they moved their datacenter to be next door to the exchange's datacenter just to reduce latency.

Exactly. At an investment bank for which I used to work in NYC, they moved their datacenter to be next door to the exchange's datacenter just to reduce latency. Because in HFT, every fraction of a second can mean the difference between 10s or even 100s of millions of dollars in profit/loss.