It’s difficult to draw correlations to organic traffic due to the penguin update that is plaguing the seo industry, however organic search has climbed 5.5% over the last thirty days compared to the previous thirty. Additionally our bounce rate has dropped slightly, time on site has jumped by 3% and pages per visit is up as well.

On submit you can tell facebook where to send the resulting data. In this class we are pointing things at web-op.com/fblogin.php.

You can view it in action here

Varnish works by loading up your static content into memory – effectively eliminating any disk i/o constraints (which are common on AWS – especially on EBS backed instances). As no disk seek is necessary – the only function varnish does is checks to see if the content requested is in the cache (in RAM) and serve it to the end user. Working from memory is much faster than reading from a disk.

[Jack notes...] Be aware that there are often assets you don’t want cached on your site. On Windshield Guru, visitors are presented with a map of nearby shops, looked up from their IP address. Obviously, this doesn’t help when they show a cached map of Washington state and you’re in Phoenix. What we chose to do is isolate these assets as iframes, and then serve them up from a seperate subdirectory with a less liberal caching policy, so every user gets them fresh. Other alternatives include drawing the info in client side with AJAX calls from a script not tied to the main caching rules.

The Results

Time to first byte dropped from 0.665 seconds to 0.029 seconds – a 2200% reduction. Overall page load time dropped from 2.547 seconds load time on first visit to 1.393 seconds – a 46% decrease!

2.547s Load Time via Apache

1.393s Load Time via Varnish

This second little scriptlet first checks for the existence of a cookie variable “BTDT”. If it doesnt find BTDT in any cookie contents it sets the cookie, checks to see if the visitor arrived from adwords and then forwards the visitor to a random split test variant. If its not an adwords visitor it does nothing. If it does find a cookie it does nothing.