performance of post_exists

Question

I have a post publish program run like this:

if (!post_exists($title)) :

$my_post = array(
    'post_title'=>$title,
    'post_content'=>'my contents',
    'post_status'=>'draft',
    'post_type'=>'skarabeepublication',
    'post_author'=>1,
);
wp_insert_post($my_post);

endif;

That is ,check if the title already exists before wp_insert_post actually publish it.

But the problem is I got 50,000 + posts on my site ,so it's very slow.

Do you know way to improve it?

I also tried:

get_page_by_title( $page_title, $output, $post_type );

It's slower than the post_exists:)