Title: PHP Fatal error – undefined function wp_cache_supports Last modified: September 12, 2023 --- # PHP Fatal error – undefined function wp_cache_supports * Resolved [Web Generation](https://wordpress.org/support/users/webgenerationnz/) * (@webgenerationnz) * [2 years, 8 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/) * I was installing this plugin on a few different sites today to compare the hosting and some sites were unable to run a benchmark test. The following PHP error was output to the error log for a site using WP 5.9.7 and PHP 7.4.33 * [12-Sep-2023 00:14:51 UTC] PHP Fatal error: Uncaught Error: Call to undefined function wp_cache_supports() in /home/mysite/public_html/wp-content/plugins/wpbenchmark/ class.wpbenchmarkio.php:1193 Stack trace: 0 /home/mysite/public_html/wp-content/ plugins/wpbenchmark/class.wpbenchmarkio.php(459): wpbenchmarkio->local_wp_cache_flush() 1 /home/mysite/public_html/wp-content/plugins/wpbenchmark/class.wpbenchmarkio. php(448): wpbenchmarkio->reset_and_prepare_object_cache() 2 /home/mysite/public_html/ wp-content/plugins/wpbenchmark/class.wpbenchmarkio.php(34): wpbenchmarkio->get_initial_steps() 3 /home/mysite/public_html/wp-content/plugins/wpbenchmark/wp-benchmark-io.php( 951): wpbenchmarkio->request_new(Array) 4 /home/mysite/public_html/wp-settings. php(418): include_once(‘/home/mysite/publi…’) 5 /home/mysite/public_html/wp-config. php(110): require_once(‘/home/mysite/publi…’) 6 /home/mysite/public_html/wp-load. php(50): require_once(‘/home/mysite/publi…’) 7 /home/mysite/public_html/wp-admin/ admin.php(34): require_once(‘/home/mysite/publi…’) 8 /home/mysite/public_html/ wp-admin/tools.php(40 in /home/mysite/public_html/wp-content/plugins/wpbenchmark/ class.wpbenchmarkio.php on line 1193 Viewing 6 replies - 1 through 6 (of 6 total) * Thread Starter [Web Generation](https://wordpress.org/support/users/webgenerationnz/) * (@webgenerationnz) * [2 years, 8 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17042973) * Screenshot of the error as shown in the front end: * > [WordPress Hosting Benchmark tool frontend error](https://imgur.com/IGtaDaz) * [vasek608](https://wordpress.org/support/users/vasek608/) * (@vasek608) * [2 years, 6 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17202145) * Please any update on the reported issue? I have tested the plugin on my 5 wordpress installations and it worked only on one. All of them are running php 7.4.33 ( ie. even the one where plugin works ok(!), so php 7.4.33 itself might not be the culprit). Perhaps plugin requires some php component, which is sometimes installed/activated on server (and sometimes not)? If so, please which php component is required (so I can activate it in server parameters)? * Many thanks * Error: * 2023-11-14T22:28:09+00:00 CRITICAL Uncaught Error: Call to undefined function wp_cache_supports() in /home/mysite/domains/mysite.ch/public_html/wp-content/ plugins/wpbenchmark/class.wpbenchmarkio.php:1193 Stack trace: #0 /home/mysite/ domains/mysite.ch/public_html/wp-content/plugins/wpbenchmark/class.wpbenchmarkio. php(459): wpbenchmarkio->local_wp_cache_flush() #1 /home/mysite/domains/mysite. ch/public_html/wp-content/plugins/wpbenchmark/class.wpbenchmarkio.php(448): wpbenchmarkio- >reset_and_prepare_object_cache() #2 /home/mysite/domains/mysite.ch/public_html/ wp-content/plugins/wpbenchmark/class.wpbenchmarkio.php(34): wpbenchmarkio->get_initial_steps()# 3 /home/mysite/domains/mysite.ch/public_html/wp-content/plugins/wpbenchmark/wp- benchmark-io.php(951): wpbenchmarkio->request_new(Array) #4 /home/mysite/domains/ mysite.ch/public_html/wp-settings.php(391): include_once(‘/home/mysite/…’) #5/ home/mysite/domains/mysite.ch/public_html/wp-config.php(96): require_once(‘/home/ mysite/…’) #6 /home/mysite/domains/naturau in /home/mysite/domains/mysite.ch/ public_html/wp-content/plugins/wpbenchmark/class.wpbenchmarkio.php on line 1193 * Plugin Author [Anton Aleksandrov](https://wordpress.org/support/users/antonaleksandrov/) * (@antonaleksandrov) * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17304425) * Sorry guys, looks like I kinda missed this place for support.. * Are you still experiencing this? What is your setup? I have never seen this sort of errors on any of sites, where I use it.. What PHP version are using? Any specific extra plugins you might have? maybe drop me a line to info at wpbenchmark dot io ? * Plugin Author [Anton Aleksandrov](https://wordpress.org/support/users/antonaleksandrov/) * (@antonaleksandrov) * [2 years, 4 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17307502) * that is quite strange – mentioned function is WordPress function and question is – why could your WP installation miss it.. it is not listed as “deprecated”.. [https://developer.wordpress.org/reference/functions/wp_cache_supports/](https://developer.wordpress.org/reference/functions/wp_cache_supports/) * but sure – i’ll add extra check for that one, although it would affect object cache benchmarks.. * Plugin Author [Anton Aleksandrov](https://wordpress.org/support/users/antonaleksandrov/) * (@antonaleksandrov) * [2 years, 4 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17307590) * Try with latest version 1.3.6. I wonder what MySQL version you have.. I have fixed some warning from table definition, besides that I did not discover any issues. * Plugin Author [Anton Aleksandrov](https://wordpress.org/support/users/antonaleksandrov/) * (@antonaleksandrov) * [2 years, 3 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17452981) * this was fixed Viewing 6 replies - 1 through 6 (of 6 total) The topic ‘PHP Fatal error – undefined function wp_cache_supports’ is closed to new replies. * ![](https://ps.w.org/wpbenchmark/assets/icon-256x256.gif?rev=2669206) * [Hosting Benchmark tool](https://wordpress.org/plugins/wpbenchmark/) * [Frequently Asked Questions](https://wordpress.org/plugins/wpbenchmark/#faq) * [Support Threads](https://wordpress.org/support/plugin/wpbenchmark/) * [Active Topics](https://wordpress.org/support/plugin/wpbenchmark/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/wpbenchmark/unresolved/) * [Reviews](https://wordpress.org/support/plugin/wpbenchmark/reviews/) ## Tags * [PHPError](https://wordpress.org/support/topic-tag/phperror/) * 6 replies * 3 participants * Last reply from: [Anton Aleksandrov](https://wordpress.org/support/users/antonaleksandrov/) * Last activity: [2 years, 3 months ago](https://wordpress.org/support/topic/php-fatal-error-undefined-function-wp_cache_supports/#post-17452981) * Status: resolved