Title: Function Perflab_Server_Timing::send_header was called incorrectly
Last modified: March 14, 2025

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# Function Perflab_Server_Timing::send_header was called incorrectly

 *  [jwriley](https://wordpress.org/support/users/jwriley/)
 * (@jwriley)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/function-perflab_server_timingsend_header-was-called-incorrectly/)
 * Seeing this on my staging server where I show errors and notices. Page seems 
   to otherwise be rendering just fine.
 * `**Notice**: Function Perflab_Server_Timing::send_header was called **incorrectly**.
   The method must be called before headers have been sent. Please see [Debugging in WordPress](https://developer.wordpress.org/advanced-administration/debug/debug-wordpress/)
   for more information. in **/var/www/our-wordpress/html/wordpress/wp-includes/
   functions.php** on line **6114**`

Viewing 1 replies (of 1 total)

 *  Plugin Author [Weston Ruter](https://wordpress.org/support/users/westonruter/)
 * (@westonruter)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/function-perflab_server_timingsend_header-was-called-incorrectly/#post-18362165)
 * If you go to the Tools > Server-Timing screen in the wp-admin (`/wp-admin/tools.
   php?page=perflab-server-timing`), make sure you have the “Enable output buffering
   of template rendering” checkbox enabled. It is most likely unchecked on your 
   site, while at the same time you have an action or filter in the textboxes below
   which refer to a hook that is called while the template is rendered.

Viewing 1 replies (of 1 total)

The topic ‘Function Perflab_Server_Timing::send_header was called incorrectly’ is
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 * 1 reply
 * 2 participants
 * Last reply from: [Weston Ruter](https://wordpress.org/support/users/westonruter/)
 * Last activity: [1 year, 2 months ago](https://wordpress.org/support/topic/function-perflab_server_timingsend_header-was-called-incorrectly/#post-18362165)
 * Status: not resolved