{"id":854,"date":"2021-03-17T06:45:05","date_gmt":"2021-03-17T06:45:05","guid":{"rendered":"https:\/\/vwo.com\/product-updates\/?p=854"},"modified":"2024-06-26T13:19:07","modified_gmt":"2024-06-26T13:19:07","slug":"vwo-performance-enhancements-reduce-impact-on-pagespeed-score","status":"publish","type":"post","link":"https:\/\/vwo.com\/product-updates\/vwo-performance-enhancements-reduce-impact-on-pagespeed-score\/","title":{"rendered":"VWO\u2019s Performance Enhancements Reduce Impact on PageSpeed Score"},"content":{"rendered":"\n

VWO has rolled out an update that would apply A\/B testing<\/a> changes on your web property even faster by prioritizing them over non-critical payload (example: libraries responsible to track visitors\u2019 behavior on your site for VWO Insights<\/a>).<\/p>\n\n\n\n

With this update, VWO reduces the Blocking Time<\/strong> as observed on benchmarking websites such as PageSpeed Insights Score (PSI score) by Google<\/a> when measured for mobile devices (default score shown by PSI). VWO’s impact on the desktop has been negligible, and with this update, we reduce the impact even on mobile PSI score. A better PSI score in turn reduces impact of using VWO on SEO for your website<\/p>\n\n\n\n

As mentioned earlier, this is done by delaying the non-critical payload until the website is completely loaded. The impact of this improvement on PSI score is highlighted later in the document and you also get a way to try this on your own.<\/p>\n\n\n\n

This change shows significant improvement over blocking time analyzed by our internal tests, observations reported by our customers, and analysis done by some people on the web such as this one<\/a> (this article claimed that average impact of VWO was 158ms at the time of publishing this article, this number should significantly reduce if the author re-runs the tests after we released this enhancement). <\/p>\n\n\n\n

The most important resources that are required to be loaded when your website first loads are the A\/B testing changes as they have to be applied on the page before the page becomes visible to the visitor. VWO now prioritizes these changes and only loads them after the website is fully loaded. We add a delay of 5 seconds after window.load. If you think a lower delay would work for your website, reach out to support@vwo.com<\/a> and we will help you configure this. We found that in 99 percent of cases, setting the time at 5 secs resulted in the best performance, and VWO by default does not show recordings less than 5 secs, so we opted for this as a safe default.<\/p>\n\n\n\n

After this, the other libraries and files, such as the ones responsible to show a survey<\/a> on the page or the ones responsible to track heatmap<\/a> and session recordings<\/a> are loaded.<\/p>\n\n\n\n

This change does not have any impact on how any of these capabilities work on your website but it will slightly delay the loading of these libraries. It means that visitors that land on your website and leave it immediately (bounce off) will not be tracked by VWO Insights.<\/p>\n\n\n\n

This change is currently enabled on mobile devices as it ensures that only critical files are loaded alongside the website resources and ensures that low network bandwidth does not hinder your website performance on mobile devices. The impact of loading all files at the same time does not hinder performance on desktop as more bandwidth in terms of computational power as well as network is available on desktop devices.<\/p>\n\n\n\n

To summarize:<\/p>\n\n\n\n