Thanks Stephen Fry!

We are supporting the team at www.explorebipolar.org by hosting the website for their event, a cycle challenge from Lands end to John O'Groats - Off Road!!! They leave at the end of the month, so good luck from all of us!

Being a supporter of all things charitable, and also a sufferer of Bi-Polar disorder himself, Stephen Fry promised to post a message on Twitter wishing the guys good luck - great!

Stephen Fry has nearly 4.5 million followers on Twitter, so we received this stark warning - 

WARNING: When Stephen tweets a URL to a given website, up to 3-000-500,000 people will attempt to visit that website within one hour. Very few websites can manage that intense traffic as the majority of it is within the first few minutes. Your website, it must be able to capable of taking 1200+ calls per second to the website’s server in order to be able to stay live once Stephen’s Tweeted. Please check with your website server provider. Many providers will simply say “Yes it is”. You must double check with a technician for your website.

1200+ hits per second is a lot for a server to deal with... However we like a challenge here at Mr Zen...

The site is running on Joomla, which requires database hits for each page request so we set about scaling up the Joomla application...

1. We aggressively cached everything we could, so that the site was hitting the database as little as possible.

2. We offloaded all of the non dynamic content (the images etc) to a CDN, or Content Distribution Network. This meant that the webserver only had to deal with requests for pages, not images, javascript files and so on.

3. We moved the server to it's own instance on the AWS Cloud - this allows us to scale up or down the server with only a few moments down time and meant that none of our other websites would be affected during the testing or the tweet itself...

4. We then scaled up the server to the max - 24 virtual cores, 80GB of RAM - wow! geek heaven...

5. We then load tested it from all of our other servers, hitting it with 300 concurrent requests from 3 different servers..

6. We tuned the web server configuration, and waited for the tweet!

He tweeted at around 0930 this morning and I'm pleased to report everything is holding up just fine...