Scaling and Tools Diversity: Google vs. Facebook

Steve Yegge in one of his posts talks about Google’s policy of standardizing on the use of only a few programming languages. He mentions how he, as a guy interested in different languages, was at first annoyed by that fact, but later came to realize it was the only sensible way of building systems as scalable as theirs have to be.

In what seems to contradict that view, in Facebook’s recent discussion of the decisions they had to make when designing Facebook Chat, they mention choosing Erlang because, well, it was made to do distributed, realtime systems with… message passing. Can’t get a better fit for a Chat project than that.

To make that code interface with their existing codebase, they used Thrift, their free software “framework for scalable cross-language services development”, whose white paper begins with the strong remark:

“In our implementation of these services [Facebook], various programming lan-
guages have been selected to optimize for the right combination of performance, ease and speed of development, availability of existing libraries, etc. By and large, Facebook’s engineering culture has tended towards choosing the best tools and implementations available over standardizing on any one programming language and begrudgingly accepting its inherent limitations.“

Now, of course Google and Facebook have very different needs (crawling, storing, rating and indexing the whole web on a regular basis must be a bit more challenging than showing user profiles — even if it’s showing many of them, many many times a day), and playing safe has surely worked out well for Google so far. But sometimes that requires reimplementing Ruby on Rails in Javascript just to suite a company requirement.

It’s good to see there is a place in the monster-traffic world for programming language enthusiasts :)