Caching issues with mobile devices

kondrich

Hi,

we are experiencing some strange caching issues with mobile devices.
If we make changes to an article and save it, we know to purge all caches in Joomla via System Configuration (or easier using the clean cache button of Regular Labs plugin "Cache Cleaner") to make it visible to the site users.

This is well-known and is working – but only for devices using desktop resolution/site version.

If we are visiting the site with a mobile device like a smartphone or a tablet, we still see the old version of the article. Even with cleaned caches. This also occurrs when visiting this particular article for the first time using this device. So it's not a cache problem on the mobile device. The mobile device gets wrong data from the server.
It does not help to clean browser cache or to long-press the reload button on the mobile device. It will still get an outdated version of the article/site.

There is just one thing that helps in this case: I have to recycle (or restart) the IIS application pool. Then the server will deliver the new version of the article even to mobile devices.

I think that we never experienced this with Fubix/T3 Framework before.
Of course the web server is caching something, yes PHP has OpCache enabled to speed up things and WinCache is also configured. But it was and is properly configured since years!
And if it really was a server (configuration) issue, why does it just affect mobile devices that receive responsive version of the site?

What could be the reason for this odd behavior?

saguaros

Hi kondrich

Could you tell me the article + the changes so I can check?

kondrich

saguaros
Yesterday, it happened in article https://www.ulc-moedling.at/news/wettkaempfe/stadionwettkaempfe/1473-nachwuchs-besucht-linz after adding the U10 section.

It got visible after recycling/restarting the website application pool (= IIS worker process). Deleting the Joomla cache did not help.

I tried to reproduce it now. It seems that it somehow has to do where you edit the article. It's fine when editing via backend editor. But editing via frontend editor leads to described behavior.

Please see the article above. Desktop site shows the last sentence as: "In der Gesamtwertung landete er auf dem guten 11. Platz und er war der Zweitbeste des jüngeren Jahrgangs 2013." i.e. with a dot at the end of the sentence.
My mobile phone shows it as "In der Gesamtwertung landete er auf den guten 11. Platz und er war der Zweitbeste des jüngeren Jahrgangs 2013!" with an exclamation mark which was the previous version.

I logged in via frontend, edited the article, saved it, checked it on my smartphone (no change), checked it on desktop site (no change), cleaned Joomla cache, checked it on my smartphone (no change), checked it on desktop site (new version is visible).

Update 10:45: I just fixed a typo in this sentence using the backend editor, saved, cleaned cache and the behavior is: The new version of the sentence is visible via desktop, but not via mobile phone. My mobile phone still displays the old version of the sencence without the two changes (exclamation mark to dot and corrected typo) even when using another browser that never displayed this article before.

saguaros

kondrich

Thanks for the detailed explanation, let me check and will get back to you.

kondrich

saguaros
Now the latest version is also displayed on mobile devices.

I just updated Joomla to the latest version 3.9.28 released yesterday. Unfortunately, I did not check it right before.
And PHP OpCache was also restarted during the night. So I do not know what it triggered it to become visible.

saguaros

kondrich It may due to the cache here, let me check and will get back to you.

kondrich

saguaros Do you have any updates concerning this topic?

kondrich

Did you install FF explorer, a file explorer component? You could use already installed ProFiles instead of installing another component.

saguaros

kondrich Yes, I installed it to manage the files, it's a file manager component developed by our developer so don't worry, I will uninstall it once it's done.

P/s: it's light and easy to use, you can give it a try 🙂

saguaros

kondrich It's weird issue and our developer is looking at this. I will update here when having news.

Appreciate your patience on this.

saguaros

I think the issue comes from the 'wincache' settings on your site, could you share the cPanel hosting info also?

kondrich

Sorry, I missed your last reply at the end of July.

I just realized that is working now. However, many components have changed: I moved to PHP 8.0.X that does not use WinCache (to answer your question; WinCache is not available for PHP 8), I updated Joomla to 3.10.1, Flix is on version 2.0.0 and T4 Framework is on version 2.0.3.

So whatever fixed it: I am happy with it.

saguaros

kondrich Glad to hear that!