WooCommerce 3.5.0 & SmushPro Conflict

I use WooCommmerce on my site to sell products. WooCommerce was recently updated to version 3.5.0 which enabled on-the-fly image resizing for the products.
This is causing Smush to get worked up and get very resource intensive to an extent that it affects the browseability of the site.
I have escalated this with WooCommerce team and they have also reached out to their developers. I am reaching out to you guys also in order to bring your attention to this.
As of now, I have downgraded the WooCommerce plugin and everything is working fine, but I will not be able to maintain this for a long time.

  • Adam Czajczyk

    Hi Michael

    I hope you're well today and thank you for your question!

    I must say that I also wasn't able to replicate this on my test setups. With the newest WooCommerce and Smush Pro I didn't notice any issues and the site wasn't going down (and I'm testing this on quite a simple and cheapo shared host).

    I'm not saying there's no conflict but I think it's more into it than solely these two plugins just being enabled. I assume that either it's some additional plugin involved or it's related to specifics of the store/smush configuration.

    I understand that you didn't have WP debugging enabled on site when this crash happened, right? It would be good to check it, though, as it could help us identify the cause or at least give additional clue on how to replicate this.

    I realize that you might not want to risk that on your live site again so would it be possible that you setup a staging site? Such a site should be an exact copy of the live one, on the same server. Then, adding following lines to the "wp-config.php" file of it would enable WP debugging:

    define( 'WP_DEBUG', true);
    define( 'WP_DEBUG_LOG', true);
    define( 'WP_DEBUG_DISPLAY', false);

    After they are added, the WooCommerce would have to be updated there and once the site crashes, there should a "debug.log" file appear inside the /wp-content/ folder (of that staging site, of course).

    Could you give it a go and then share that debug.log file with me here? You can upload it into some file storage of yours (e..g Google Drive or Dropbox or similar) and just post a download link to it here.

    Hopefully, that would give us a clue (without affecting your live site!) on what might be happening there. Then we'd see what to do next to pinpoint the source of the issue and how to fix it.

    Best regards,

  • Michael

    Hi Adam,
    Thank you for the clear guidance. As instructed I have set up a staging site and generated the debug.log file for your reference (see attached).
    Although the Gateway Error did not appear when I tried opening a few product pages, I believe that was because the page load time did not exceed the 60 second limit imposed by my hosting provider. Page load times were very slow however, and I guess somewhere in the range of 30 seconds per page depending on how many images were in the product image gallery.

    Please let me know if you need anything else.


  • Adam Czajczyk

    Hi Michael

    Thank you for your response and for sharing a debug.log. There is a notice in the log but it's not related to Smush Pro and doesn't seem to be a reason for such slowdown anyway. I have also checked our internal reporting system but didn't find anything related to the case.

    I'll need to "dig deeper" then. Since you already setup a staging site, could you please enable support access to that staging site too? I would also like to be able to access its files and database so a cPanel access would be perfect (or FTP + phpMyAdmin access, but cPanel is preferred if available). After enabling support access to the staging site, you may put these credentials safely in a text box below "Access active for X days" message on "WPMU DEV -> Support" page. The message won't be posted anywhere so just let me know here once you're ready and I'll try to find out what's happening.

    Best regards,

    • Anton Vanyukov

      Hi Michael ,

      I have tried to replicate on my test sites, but was unsuccessful. Also, I have looked at your staging website. It does load slowly, but not because of Smush, because Smush does not optimize images on the frontend. I would recommend you do a plugin conflict test and find the conflicting plugin. Plugin conflict test is disabling all the plugins, and enabling them one by one to find which one is causing the issue.

      Also please update Smush to the latest version, as it includes fixes for WPML compatibility.

      Best regards,

  • Michael

    Thanks for the follow-up Predrag/Anton.
    As instructed I have uploaded the php file to the specified folder and tried browsing a few product pages. All the pages appear to be loading normally again, so I can only assume that the issue has been resolved. Thanks very much!

    I have a number of other sites using Smush as well, so if you could let me know when you plan to release this update it will help me decide when to re-activate the plugin on those sites.

    Many thanks,


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