In a recent blog post, I wrote about a Facebook widget slowing down Lenny Kravitz’s new web site.

To drill into this a bit more, I decided to monitor performance of just that asset – monitoring the Facebook widget using Yottaa’s network of real browsers located across the planet. The goal was to assess:

1. What is the nominal performance of the widget?
2. How reliable is it?
3. How often are there performance outliers, and how bad are they?

The Data

After setting up the monitor and waiting a few days, Yottaa collected thousands of samples. Here?s a scatter plot of the Time to Interact metric.

I decided to define 3 key issues (with corresponding alerts that can be delivered via email or SMS):

So how did Facebook do? Well, on average the widget is fairly robust, though there is definitely occasional performance problems.

The widget typically pops up in just about half a second (458 msec). But, there are the occasional outliers, as seen on the scatter chart above. So, I wanted to drill into the data further. One cool feature we recently rolled out is the ability to export any metrics collected. So, I exported the data into Excel and did some analysis. From the histogram, we see that approximately 3.5% of the samples are above one second (in fact, sometimes reaching 30 seconds, likely during traffic spikes for the Facebook widget).

And, to get a sense as to how this varies around the world, here’s the performance by geography: both the average value, and the standard deviation (as an indicator of just how much variability there is in that location).

It’s interesting to note that there’s quite a bit of variation in performance: In Tokyo, the widget loads quickly, with a very small amount of variation; on the other hand, Sao Paolo are 2-4X slower, with an order of magnitude more spread.

Alerting & Notification

Yottaa Site Monitor kept me notified whenever the widget encountered any of the issues I defined above.

So What Can You Do to Address This?

Well, if you’re on the Facebook infrastructure team, you may want to look into the variability in the widget’s performance! 🙂 In fact, it’s ironic that while Facebook does a ton of things to make THEIR site fast, their widgets tend to make OTHER sites slower.

Otherwise, if you’re responsible for a website that relies on the FB widget, you can minimize the performance hit by loading it asynchronously.

And the broader point is: there are a lot of reasons a site can go down, so monitoring, alerting, deep-dive analysis and troubleshooting are invaluable tools that are now within reach of any company, rather than Internet giants like Amazon and Facebook.