Load Balancing on the Cheap

A few months ago, we started to look at alternate load balancing methods for our site. At the time, we had a pretty basic setup using Nginx. While this worked for the most part, our setup lacked some of the nicer features of a traditional load balancer such as health checks and automated removal of poorly responding backend servers. This meant that every time a backend server went down, there would be some, however minor, user visible impact until we it could be removed from rotation.

Thus, began the search for a new solution. Our requirements were fairly simple:
- easy to setup and understand
- ability to health check and automatically remove failing servers
- low cost

From here, additional features would be a bonus, but not required for our immediate goals. After looking at several solutions, we settled on using HAProxy, an opensource and free solution.

The benefits were noticeable almost instantaneously. One of the first observations was that hosts behind HAProxy were able to serve the same amount of traffic, but with a lower load average. What we surmised is that there was less setup/teardown of tcp connections which freed up system resources to actually serve user requests. Once we finished our full migration, we actually saw the loads on our webservers drop nearly in half, which allowed for more growth on our existing infrastructure.

In the weeks that followed, we started to take advantage of additional features provided by HAproxy. For example, the status page also has a csv output option. By parsing this and doing some small calculations, we are able to see the various states of our servers and get an overall percentage of our serving capacity. It's well known that computers go down, it's just the nature of things. By utilizing cluster wide checks, we don't have to get alerted for a single host down, but rather if a large amount of capacity is down.

Enough of talking about some of the features, let's take a look at a configuration example.

Let's say you have 5 web servers: web1, web2, web3, web4, web5. A basic HAproxy configuration would look like this:

global
log 127.0.0.1 local0
log 127.0.0.1 local1 notice
maxconn 1024
chroot /var/lib/haproxy
user haproxy
group haproxy
daemon
#debug
#quiet

defaults
log global
mode http
option httplog

listen webservers :80
mode http
server web1 web1:80 weight 1 check inter 15s
server web2 web2:80 weight 1 check inter 15s
server web3 web3:80 weight 1 check inter 15s
server web4 web4:80 weight 1 check inter 15s
server web5 web5:80 weight 1 check inter 15s

All done! You now have a load balancer that distributes requests among 5 servers and checks every 15 seconds to see if their ports are responsive.

For more information on HAProxy and configuration options, check out their website.

Lolapps Launches Champions Online for Facebook

If you're a fan of Inside Social Games, odds are you've heard about our Facebook version of the game, Champions Online, launching Wednesday, the 18th. We're very excited about the launch and the great feedback we've received so far! According to AppData, the game already has over 700,000 users and is ranked ninth on the top rising Facebook app list for today (as high as fifth). We're hoping these numbers are just a prelude of what's to come.

To give you some background, this game is a result of a recent partnership between Lolapps andAtari's Cryptic Studios that was fostered to extend the Champions Online brand to the Facebook platform. We believe this partnership creates a win-win situation for users, Cryptic and Lolapps as it blends our expertise as one of the marquee social gaming companies along with Cryptic Studios and Atari, who have a long history of creating extremely successful gaming titles. Cryptic Studios is behind such acclaimed games as Star Trek Online, City of Heroes and City of Villains, while Lolapps is amongst the top five application companies on Facebook in terms of user reach. Between such excellent intellectual properties and prodigious distribution, Facebook users can look forward a new calibre of social gaming.

If you are curious about what the game is like (and are unfamiliar with the original version of Champions Online) here is a quick look at the game's story line:

"You are a brave superhero, aka a Champion, who helps protect the world from evil wrongdoers. The Sinister Syndicate, a gang of some of the world's most dastardly villains have come together to destroy the world! With the guidance of Socrates, the all-knowing supercomputer, you travel the Champions universe; from futuristic Millenium City, to frigid Canada, to Monster Island, Atlantis, and to many more fantastic locations, in an effort to put an end to the Sinister Syndicate's diabolical plan. Complete heroic tasks, acquire superpowers, and save the world one villain at a time... it's just a day in the life of a Champion!"

Through this game, you can see that we've built an extremely robust platform that allows us to work collaboratively with our partners and introduce both existing and new brands to our users. We are bridging the gap between social networks and traditional game developers to open up the Facebook doors for players like Cryptic.

Looking to expand your current audience and expose your game to millions of new users? Drop us a line at bizdev@lolapps.com!

Check out more about the game on Inside Social Games or become a Champion yourself and start playing!