Facebook numbers

A few of the big numbers we deal with:
* 500 million active users
* 100 billion hits per day
* 50 billion photos
* 2 trillion objects cached, with hundreds of millions of requests per second
* 130TB of logs every day

Over the years we've written on this page about a number of the technical solutions we've used to handle these numbers. Today, I'd like to step back and talk about some of the general ways we think about scaling, and some of the principles we use to tackle scaling problems. Like Facebook itself, these principles involve both technology and people. In fact, only a couple of the principles below are entirely technical. At the end of the day it's people who build these systems and run them, and our best tools for scaling them are engineering and operations teams that can handle anything. The scaling statistic I'm most proud of is that we have over 1 million users per engineer, and this number has been steadily increasing.