How to change file loading and transfer capacity in Wordpress

Try adding set_time_limit to wp-config.php

set_time_limit( 600 );

Add the following code to your config.php file.

@ini_set('upload_max_filesize' , '256M');
@ini_set('post_max_size', '256M');
@ini_set('memory_limit', '512M');
@ini_set('max_execution_time', '600');
@ini_set('max_input_time', '600');

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Add the following code to your config.php file.

@ini_set('upload_max_filesize' , '256M');
@ini_set('post_max_size', '256M');
@ini_set('max_input_time', '600');

With a code or text editor, add the following code to your existing or new php.ini file:

upload_max_filesize = 32M
post_max_size = 64M
memory_limit = 128M

Create or Modify the .user.ini File

If your hosting provider has locked down the global PHP settings, they may have configured the server to work with .user.ini files instead of php.ini files.

upload_max_filesize = 32M
post_max_size = 64M
memory_limit = 128M

Increase the Max Upload File Size in Nginx

On an Nginx server, you can find the php.ini file at /etc/php/7.4/fpm/php.ini. Depending on which PHP version you’ve installed, the exact path may vary slightly.

upload_max_filesize = 64M
post_max_size = 128M

Use the WordPress ‘upload_size_limit’ Filter

Below is an example of this filter in action from WordPress contributor Drew Jaynes. It defines the upload size limit for all non-admin roles.

/**
* Filter the upload size limit for non-administrators.
*
* @param string $size Upload size limit (in bytes).
* @return int (maybe) Filtered size limit.
*/
function filter_site_upload_size_limit( $size ) {
// Set the upload size limit to 10 MB for users lacking the 'manage_options' capability.
if ( ! current_user_can( 'manage_options' ) ) {
// 10 MB.
$size = 1024 * 10000;
}
return $size;
}
add_filter( 'upload_size_limit', 'filter_site_upload_size_limit', 20 );