Heroku: Up and Running

Chapter 4. Heroku Regions

These days, everything is global. Only 20 years ago a business may have limited its area of operation to only those places within a few hours’ travel. Today, however, it is possible to trade globally and instantly. As for your applications, this means that you can interact with anyone, anywhere (your user base might consist of people in the United States, Europe, Australia, and Asia all at once).

So, what difference does this make to you? All of those users can access your application and use it—everything’s fine, right?

Well, for starters, let’s consider latency. Data travels down the pipe pretty fast, but there is a noticeable delay when working at very large distances. For instance, an application hosted on the eastern seaboard of the United States accessed from the United Kingdom has a latency of around 100 ms. The same application hosted in Europe, which is around 3,000 miles closer, only has a latency of around 20 ms.

When you are trying to wring every bit of performance from your application, this latency is not to be sniffed at—it’s a sizable performance saving, and more or less for free. Just by changing where your application is physically can make a huge impact on your application performance and the happiness of your users.

So, what other reasons might there be for moving your application around the world? For instance, some nations or regions have laws in place to protect their citizens and limit what people can do with their data. For instance, ...