Title: Error on PHP8.1 on WP Memory Usage
Last modified: February 19, 2023

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# Error on PHP8.1 on WP Memory Usage

 *  Resolved [PowerMan](https://wordpress.org/support/users/powerman/)
 * (@powerman)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/)
 * Warning: Undefined array key “mb” in /wp-content/plugins/wp-memory-usage/wp-memory-
   usage.php on line 69
 * Warning: Undefined array key “unity” in /wp-content/plugins/wp-memory-usage/wp-
   memory-usage.php on line 70

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Plugin Author [berkux](https://wordpress.org/support/users/berkux/)
 * (@berkux)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/#post-16485025)
 * Thank you. I‘ll check that.
 * Bernhard
 *  Plugin Author [berkux](https://wordpress.org/support/users/berkux/)
 * (@berkux)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/#post-16485039)
 * This happens when WP_MAX_MEMORY_LIMIT is not set at a wordpress installation:
   no “define( ‘WP_MAX_MEMORY_LIMIT’, ‘256M’);” in wp-config.php
   The next Version
   of this plugin will fix that setting of the variable. Bernhard
 *  Plugin Author [berkux](https://wordpress.org/support/users/berkux/)
 * (@berkux)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/#post-16485135)
 * Check version 1.2.8, please
 *  Thread Starter [PowerMan](https://wordpress.org/support/users/powerman/)
 * (@powerman)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/#post-16485379)
 * Great, now it works. Thanks for the quick update.

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Error on PHP8.1 on WP Memory Usage’ is closed to new replies.

 * ![](https://ps.w.org/wp-memory-usage/assets/icon-256x256.png?rev=3474934)
 * [WP-Memory-Usage](https://wordpress.org/plugins/wp-memory-usage/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/wp-memory-usage/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/wp-memory-usage/)
 * [Active Topics](https://wordpress.org/support/plugin/wp-memory-usage/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/wp-memory-usage/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/wp-memory-usage/reviews/)

 * 4 replies
 * 2 participants
 * Last reply from: [PowerMan](https://wordpress.org/support/users/powerman/)
 * Last activity: [3 years, 3 months ago](https://wordpress.org/support/topic/error-on-php8-1-on-wp-memory-usage/#post-16485379)
 * Status: resolved