Zoompf's Web Performance Blog

Note: Archived Content

This is the archived version of the Zoompf blog. Since our acquisition by Rigor, all our new research and posts on web performance are being published on The Rigor Blog

Too Many Performance Defects? 4 Ways to Cut Down the Noise

 Mark Isham on August 27, 2014. Category: Zoompf Alerts

Time is always a challenge for the performance-minded web developer. You’d love to spend all day tuning your site, but competing priorities are an unavoidable fact of life.

When we announced our new Zoompf Alerts beta last week, we mentioned one of the primary goals of Zoompf Alerts was to Find only the performance problems you care the most about. (And if you’re not on the free beta yet, you’re missing out…).

Managing the signal to noise ratio was a top priority for Zoompf Alerts from the start. When you get an alert, it should be meaningful – information of real value that you should act on now. The rest…can wait.

If you consider yourself overwhelmed with performance defects, this article is for you. In the following sections I’ll go over 4 tips to reduce the noise to a manageable level.

Tip 1: Increase Your Alert Threshold


Alert Thresholds control how severe a performance defect must be before you get alerted. The higher the threshold, the worse the defect must be. For example, if your threshold is set to high, the Content Not Compressed performance rule will only flag alerts on “Any item at least 200 KB in size which can be optimized by at least 50%, or any item with a savings of at least 200 KB.” Conversely, if you set your threshold to Low, any item with at least 15 kb of savings will alert. To see a full list of our threshold values, try changing the threshold slider in one of our Demo Accounts.

High Thresholds are designed to alert you when only the “really bad” stuff happens. Ideal for developers who have only limited time for performance tuning. As you lower your thresholds, more detail will get exposed – ideal when you’re trying to make your site as fast as possible.

Adjust the thresholds to a level that makes the most sense to your circumstance. And don’t worry, you can always change this setting later.

To access your Alert Thresholds, from your dashboard click ‘Settings’ and then the ‘Alert Thresholds’ tab.

Tip 2: Ignore Defects You Can’t Fix

Sometimes there are problems with content you just can’t fix. For example, maybe that CSS include is hosted by an external provider that will not turn on content compression. Or maybe those images are supplied by a different department and you have no say in what they publish.

While we always advise you fix as many defects as possible (your users will be the final judge), we also understand your time is limited and you need to prioritize.

Towards this end, Ignore Rules are here to help. Ignore Rules allow you to hide a specific piece of content, or even an entire domain, from all future alerts. Setting up an ignore rule is very easy, in your performance snapshot view, just click the “Ignore” icon on the far right for any result you wish to ignore.

For example:


Your alert emails also contain a similar link. Once you click ignore, you can then choose from several options controlling how much content you wish to ignore, up to and including all defects from a specific domain:


Finally, if you’re worried about “out of site, out of mind”, don’t. You get a subtle reminder about ignored defects in your performance snapshots, and always have the ability to restore ignored defects to your alerts later. For example:


Tip 3: Disable Unused Performance Rules

Beyond ignoring specific content, you can also ignore specific “types” of performance defects based on the performance rule that was violated. For example, Content Not Compressed, Content Not Minified, etc.

Say for example you have a hosting provider that gives you no control over server configuration settings, but you can still control your content and images uploaded to the host. In this scenario, you may not want to be alerted about compression or caching defects since you are powerless to fix them.

Disabling performance rules is the tool for the job here. To access, go to your Settings page and click the Alert Thresholds tab. From there, scroll down to the Performance Rules section. You’ll see a list of all the performance rules Zoompf Alerts will test your site against, with a short description and an on/off slider for each. For example,


Simply turn off the rules for which you do not want to receive alerts. Again, don’t worry as you can always change this setting again later.

Tip 4: Hide Third Party Content (3PC)

Okay this one is easy, we already do it for you. If you are including ad trackers, analytics beacons and other third party controls for which you have no ability to fix, you do not want to get alerted when their performance is sub-optimal (and it usually is).

At Zoompf we maintain an extensive database of Third Party Content domains, and even have an open source project to maintain this at ThirdPartyContent.Org.

We automatically filter out any performance defects identified for 3PC components from your results, so you don’t need to worry about them. Still, there is always new 3PC arriving so it’s a constant arms race to keep up with the latest. If you have 3PC in your results, hit the Contact link on your dashboard and tell us about it! We’ll strive to keep that database up to date as new 3PC arrives.

And if a defect within your site depends on external 3PC, we’ll also flag that dependency with a 3PC badge in your results so you can clearly see the dependency. For example:


Now of course we’re not saying you should always ignore 3PC. Your users still have to wait for it to load, so you should at least be aware of its impact. To view how much 3PC you have on your site, we highly recommend running our Free Report and you’ll get a nice breakdown of just how big an impact 3PC has on your page load time.

In Closing

With Zoompf Alerts you have the tools to balance the information density to the level that fits your working style. If you are trying to squeeze every ounce of performance out of your site, you should choose a low alert threshold and not ignore any content or performance rules. Conversely, if you have very little time to focus on performance, setting a high alert threshold with judicious use of ignore rules can help you manage your time while still providing a valuable performance safety net.

We hope you find this level of flexibility useful. And of course, if there’s more we can do always feel free to contact us!

If you’re not on the Zoompf Alerts beta, learn more and sign up for free. And if you want to run a deeper one-time performance analysis of your site, check out our free report.


Have some thoughts, a comment, or some feedback? Talk to us on Twitter @zoompf or use our contact us form.