Hey! In php, when I use `ini_set('memory_limit','6GB');`, it gives blank page? Why is that?
A blank page in PHP usually indicates a fatal error that stops the script from executing further. When you set the memory limit to '6GB' using ini_set('memory_limit', '6GB'); and encounter a blank page, it could be due to one of the following reasons:

1. Insufficient system memory: If your system does not have enough available memory to allocate 6GB to the PHP script, it may cause a fatal error.

1. PHP configuration: Some server configurations may restrict the maximum memory limit that can be set for a PHP script. Check your PHP configuration file (php.ini) to see if there's a hard limit set for the memory_limit directive.

1. Error reporting/display settings: PHP may be suppressing error messages or not displaying them on the page. You can enable error reporting and display to get more information about the issue. Add the following lines to the beginning of your PHP script:

```php
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
```

After adding these lines, run your script again and see if any error messages are displayed.

1. Web server timeout: If your PHP script takes too long to execute, the web server may time out, causing the script to stop running and returning a blank page. Check your web server's timeout settings and adjust them if needed.

To resolve the issue, you can try:

- Reducing the memory limit to a lower value, e.g., '512M', '1G', or '2G', and see if the script runs without issues.
- Checking your server's available memory and ensuring it can accommodate the desired memory limit.
- Reviewing your PHP and web server configurations for any restrictions or timeout settings that might be causing the problem.

If none of these suggestions resolve the issue, consider checking the server logs for any errors or clues about what may be causing the blank page.