Methods taking a long time

At times there are performance issues with our site and I narrowed it down to the Tiny_Plugin::ajax_optimization_statistics method and also the Tiny_Bulk_Optimization::wpdb_retrieve_images_and_metadata method

Those methods are consuming a significant amount of time, approximately 99.99% of the web transaction’s time.

Here is part of the trace that

• Custom/do_action 320.50 s 99.43%
  • Custom/WP_Hook::do_action 320.50 s 99.43%
    • Custom/WP_Hook::apply_filters 320.50 s 99.43%
      • Custom/Tiny_Plugin::ajax_optimization_statistics 320.50 s 99.43%
        • Custom/Tiny_Bulk_Optimization::get_optimization_statistics 320.50 s 99.43%
          • Custom/Tiny_Bulk_Optimization::wpdb_retrieve_images_and_metadata 38.39 s 11.91%
            • Custom/wpdb::get_results 38.39 s 11.91%
              • Custom/wpdb::query 38.39 s 11.91%
                • Custom/wpdb::_do_query 38.02 s 11.80%

This was the query that was taking some time

SELECT
				wp_posts.ID,
				wp_posts.post_title,
				wp_postmeta.meta_value,
				wp_postmeta_file.meta_value AS unique_attachment_name,
				wp_postmeta_tiny.meta_value AS tiny_meta_value
			FROM wp_posts
			LEFT JOIN wp_postmeta
				ON wp_posts.ID = wp_postmeta.post_id
			LEFT JOIN wp_postmeta AS wp_postmeta_file
				ON wp_posts.ID = wp_postmeta_file.post_id
					AND wp_postmeta_file.meta_key = ?
			LEFT JOIN wp_postmeta AS wp_postmeta_tiny
				ON wp_posts.ID = wp_postmeta_tiny.post_id
					AND wp_postmeta_tiny.meta_key = ?
			WHERE
				
				wp_posts.post_type = ?
				AND (
					wp_posts.post_mime_type = ? OR
					wp_posts.post_mime_type = ? OR
					wp_posts.post_mime_type = ?
				)
				AND wp_postmeta.meta_key = ?
			GROUP BY unique_attachment_name
			ORDER BY ID DESC
			LIMIT ? 

We were compressing new images in the background and I noticed that using that features consumes server resources instead of sending to TinyPNG’s servers to compress, so I switched to “compress new images during upload,” but that also did not resolve the issue.

Any help or insights would be great, been troubleshooting for some time to find a solution but I have not found one.

Thanks!