Web Technology Performance and Business: Making the Cut
“As technology continues to evolve, our customers/end-users are desiring more direct feedback and timely responses”
Understanding all of this, for those driving an organizations long-term application direction what truly defines a performance optimized application? If you ask the business stakeholders you will get various answers, most of which are highly subjective and hard to quantify. Commonly when I work with customers we will receive responses such as- “It must be fast”, “It must handle our 14,000 concurrent users,” or “It must take less than 3 seconds.” At first glance this seems to be somewhat easy to quantify, however, lets investigate a few common metrics used to analyze and report on page performance.
Common Page Performance Metrics
Having worked with organizations large-and-small I have found that a key to understanding performance is to first understand the metrics that can be used to gauge performance. Once these metrics are understood it is then possible to create a plan to make the best improvements overall.
Average Page Load Time (HTML Only)
Using CIOReview.com as an example I was able to confirm an average HTML only load time of 445 milliseconds.
Average Page Load Time (Full Request)
Taking the HTML only metric and looking at a more realistic value we start to see the Average Page Load Time metric coming together. If you pull up the CIOReview.com website in a web-browser it will NOT appear to load in 445 milliseconds, and that is exactly what this metric is designed to show. To properly calculate load time you need to ensure that all resources are loaded and the browser has been able to fully render the screen.
Revisiting the CIOReview.com homepage we can see a total page load time average of 7.2 seconds. This is the total time to retrieve the page, render in the browser and for all page processing to stop.
Number of HTTP Requests
Directly related to the two prior metrics it is common to report the total number of HTTP Requests needed to complete the rendering of a page. Web browsers can only download a certain amount of items at the same time, therefore a high number of requests results in longer page load times. There is no magic number that is acceptable here, but the more you have, the longer it will take for the entire site to render. It is common to use tools to combine/minify resources to optimize.
To provide a few examples, CIOReview.com requires slightly more than 223 HTTP Requests to render the homepage. Microsoft.com requires less than 80.
Requests/Second or Concurrent Users
The prior referenced metrics illustrate the time necessary to load a single resource, or a single page. As organizations look to optimize for higher traffic loads we will often see metrics reporting either Requests Per Second or the number of current users supported. Both metrics show similar information as it is easy to translate one metric into the other.
Which Metrics to Select and What Target Values?
With a little bit of background into the various metrics, which of these are truly important to your organization? The real answer here will be dictated by your specific organizational needs, but there are a few common rules of thumb.
For Search Engine Performance
Google has a published tool called “Page Speed Insights,” which allows you to analyze the performance of your website against a set of rules they have published. This tool starts to reduce points if any page load request exceeds 200 milliseconds, which gives a good target to aim for.
For User Experience
Various studies have been completed over the past decade, and a common consensus between these studies is that total page load times of greater than 2 seconds result in loss of user attention. There are exceptions to this rule, however, again it is a starting point. Login pages, or complex trigger starting points are cases where longer page load times are acceptable.
Elevating Your Organization
With a better understanding of the metrics that could benefit your organization progress becomes easy to manage and quantify. Baseline and regular performance reviews of web properties, both complex and simple, will ensure that the best presentation is made to your customers. It is important to understand that at the top level performance needs to be embraced as a long term feature and not simply a “one time” project.
Ensuring that users can obtain the information they want, when they want, is the key to any successful organization.