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Slow PageSpeed, Render Delay & LCP issue

I am working on a website. LCP and Specially Render Delay is low after all works I done on Cache, CDN and trying to not prioritizing Java Scripts.

What I am expecting is quite simple, Good Web Core Vital links.

I really appreciate your help.

Solution

  • So this may be one where the Lighthouse test results aren't as useful (in part because they have been made useless - we'll get to that).

    Always look at the real user data, and understand the breakdown between TTFB, FCP, and LCP

    You are talking about Render Delay so I presume you're talking about the LCP breakdown parts as given by Lighthouse:

    LCP breakdowns

    When I look at your real test results I see this:

    PageSpeed Insight real users are experiencing

    That is, your TTFB at 2.6 seconds is already over the good threshold of 2.5 seconds for LCP. Without improving TTFB you won't be able to make much inroads on LCP.

    There's advice here on:

    TLDR: This could either be due to how your visitors end up on your site (e.g. through multiple redirects—often a problem from ads), or that they are far away from you (so you may need to invest in a CDN to improve this), or because you are hitting the server each time as you don't cache. You'll need to look at your own analytics to understand your traffic sources to answer that.

    About 0.8 seconds after TTFB you get your FCP at 3.4 seconds And then 0.7 seconds later you get LCP.

    These aren't bad timings after LCP to be honest and if you can improve your TTFB then you will likely resolve most of the issues with them.

    Don't trick the metrics - you're only depriving yourself of information and making the experience WORSE for users

    The next major issue is that your don't show the main content (the product) until the user interacts with the page (e.g. by scrolling or pressing a button). The is why the page does not look fully formed in the Lighthouse screenshots.

    This is often done by performance plugins as a way to cheat the LCP alogorithm at the expense of the user. Great you have made your LCP metric faster, but the user experience is much, much worse. And you've not lost all visibility in knowing and being able to measure that. It also means the Lighthouse audit is useless as the site has explicitly been setup to trick it.