After enabling theme speed optimization and WP-ROCKET according to the document, homepage returns 500 if not login. Nginx error log says: "PHP message: PHP Fatal error: Unknown: Cannot use output buffering in output buffering display handlers in Unknown on line 0" while reading upstream". But homnepage seems OK if I login WP.
I have found another problem. If "Create Critical CSS?" enabled and WP-Rocket disabled, homepage will return 500 if not login. Nginx says many errors like: "FastCGI sent in stderr: "PHP message: PHP Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes) in /data/www/devbean.net/public_html/wp-content/plugins/penci-shortcodes/pagespeed/inc/remove-css/sanitizer.php on line 203" while reading response header from upstream". I have pasted the logs in attachment. But if I only disable "Create Critical CSS?", leave others as documents says, homepage looks fine except it loaded without CSS for seconds then renders as usual.
Thank you. It solved. It turns out this bug is because wp memory limits and not cause by WP-Rocket. It works great with WP-Rocket as document mentions.
After enabling theme speed optimization and WP-ROCKET according to the document, homepage returns 500 if not login. Nginx error log says: "PHP message: PHP Fatal error: Unknown: Cannot use output buffering in output buffering display handlers in Unknown on line 0" while reading upstream". But homnepage seems OK if I login WP.
Hi,
This is an error from the WP-Rocket plugin, please temporarily disable this plugin and use the W3 Total Cache instead then check again.
Regards,
PenciDesign.
I have found another problem. If "Create Critical CSS?" enabled and WP-Rocket disabled, homepage will return 500 if not login. Nginx says many errors like: "FastCGI sent in stderr: "PHP message: PHP Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes) in /data/www/devbean.net/public_html/wp-content/plugins/penci-shortcodes/pagespeed/inc/remove-css/sanitizer.php on line 203" while reading response header from upstream". I have pasted the logs in attachment. But if I only disable "Create Critical CSS?", leave others as documents says, homepage looks fine except it loaded without CSS for seconds then renders as usual.
Hi,
About this error, please follow the instruction here: https://www.wpbeginner.com/wp-tutorials/fix-wordpress-memory-exhausted-error-increase-php-memory/
Regards,
PenciDesign.
Thank you. It solved. It turns out this bug is because wp memory limits and not cause by WP-Rocket. It works great with WP-Rocket as document mentions.