How to increase php memory limits only for Drush commands in Drupal settings file

To increase the PHP memory limit for all PHP CLI (Command Line Interface) commands in Drupal, you can add a configuration to the settings.php file. Here's how to do it:

1. Open the settings.php file for your Drupal installation. This file is usually located in the sites/default folder of your Drupal installation.

2. Add the following lines of code to the bottom of the settings.php file:

   /**
    * Set PHP memory limit for CLI commands. 
    */ 
   if (PHP_SAPI === 'cli' || ) { 
     ini_set('memory_limit', -1); 
     ini_set('max_execution_time', -1); // You can do this or change any other global variables here.
   }

   This code checks if the current script is being executed in CLI mode by using the php_sapi_name() function. If it is being executed in CLI mode, it sets the PHP memory limit to -1 or infinite.

3. Save the settings.php file.

Now, whenever you run a PHP CLI command, the PHP memory limit will be set to -1. You can adjust the memory limit value by changing the value passed to the ini_set() function. Instead of the PHP_SAPI php constant, you can also use the function `php_sapi_name()`.