Get autoload heavy options from the WordPress `wp_options` ($wpdb->options) table.

get-heavy-options.php

<?php
/**
 * Get autoload heavy options from options table
 * 
 * @todo Change the `prefix_` and with your own unique prefix.
 * 
 * @since 1.0.0
 */
if( ! function_exists( 'prefix_get_heavy_autoload_options' ) ) :
	function prefix_get_heavy_autoload_options() {
		global $wpdb;

		$details = $wpdb->get_col( "SELECT `option_name`, length(`option_value`) AS `option_value_length` FROM {$wpdb->options} WHERE autoload='yes' ORDER BY option_value_length DESC LIMIT 10" );

		var_dump( $details );

		// Output: (Something similar)
		// 
		// array (size=10)
		//   0 => string 'xxxxxxxxxxxx' (length=17)
		//   1 => string 'xxxxxxxxxxxxxxxxxx' (length=23)
		//   2 => string 'xxxxxxxxxxxxxxxxxxx' (length=41)
		//   3 => string 'xxxxxxxxxxxxxx-1' (length=27)
		//   4 => string 'xxxxxxxxxxxxxx-2' (length=27)
		//   5 => string 'xxxxxxxxxxxxxx-3' (length=27)
		//   6 => string 'xxxxxxxxxxxxxxxxx' (length=23)
		//   7 => string 'xxxxxxxxxxxxxxxxxxxxxxx' (length=16)
		//   8 => string 'xxxxxxxxxxxxx' (length=13)
		//   9 => string 'xxxxxxxxxxxxxxxxxxxxxxxxx' (length=32)

		wp_die();
   	}
   add_action( 'wp_head', 'prefix_get_heavy_autoload_options' );
endif;