Building a Billion User Load Balancer [video]

This is gold.

But really, DNS load balancing can be really useful (and is so easy to set up).

I'd like to complement this comment and suggest that this practice should be applied to links that may be blocked to a grand part of us, people that are behind a firewall.

Here - I created an SRT Closed Caption file for you:

http://keepsubs.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwat...

We didn't get serious about load balancing and create a team dedicated to it until fall of 2011. At the time, Facebook had 800 million active users per month. We had run out of runway on commercial and open source options, and needed a lot more flexibility with how we allocated and moved traffic around. It took a lot of effort to get to where we are today, but the thing I'll tell you is that these huge systems always start with a prototype running on a dev server. And then you get it to run traffic for your whole team, and then the whole company. Then you try it in a cluster, a datacenter, a region, and all of a sudden you've built a load balancer.

It took Proxygen less than 18 months to go from inception at a hackathon to running all of Facebook's production HTTP traffic. And we could have shaved that by a few months if we had made smarter decisions along the way.

Not sure if the talk covered it, but the core Proxygen framework is opensource: https://github.com/facebook/proxygen

This stuff seems basic at first glance, but it's not easy to get right, and you're discounting a ton of effort that went into getting feedback loops and demand prediction to work properly in Cartographer for example. Maybe it's easy to slap together L4/L7 LB and throw a DNS server in front of it at smaller scales, but it's a notable accomplishment to do this at Facebook's scale. Nothing out there approaches Facebook's request rates.

There have been detailed talks about Proxygen's architecture at various open houses in Seattle and Menlo Park, and they should have HTTP2 support working well soon. I'd expect there's going to be more detailed blog posts on Proxygen at some point. Or you can check out the source code too.

Fragmentation isn't really an issue for either Shiv or Proxygen. I don't think they will share the rate but it is very low.

Why would I get downvoted for that? It's a serious concern. It's missing modern and often important features unless you use unofficial patchsets, and some missing entirely (NSEC3). And then there are all the forks like dbndns from Debian, N-DJBDNS, etc...

You'd be even more surprised what they used before tinydns. :D They wanted speed and robustness, and iterated over quite a few choices including roll-yer-own.

Source: I created a pilot project called "Doppler" that was eventually folded into this system. http://carlos.bueno.org/2011/07/doppler.html

It's a simple, fast DNS server that is straightforward to extend if you need to. The genius of Cartographer is that the backend that calculates where to assign traffic is separate from the DNS server frontend. This let FB use a known-good DNS server that got the common DNS protocol stuff right, and gave them more time to focus on all the magic bits in Cartographer's backend.

DNSSEC was never something we were aiming for, so it's fine that TinyDNS doesn't support it out of the box.