WordPress at a glance
filter is not described

edit_(post_type)_per_page filter-hook . WP 3.0.0

Filters the number of items per page to show for a specific 'per_page' type.

The dynamic portion of the hook name, $post_type, refers to the post type.

Some examples of filter hooks generated here include: 'edit_attachment_per_page', 'edit_post_per_page', 'edit_page_per_page', etc.

Usage

add_filter( 'edit_(post_type)_per_page', 'filter_function_name_2525' );
function filter_function_name_2525( $posts_per_page ){
	// filter...

	return $posts_per_page;
}
$posts_per_page(int)
Number of posts to display per page for the given post type.
Default: 20

Where the hook is called

wp_edit_posts_query()
edit_(post_type)_per_page
wp-admin/includes/post.php 1068
$posts_per_page = apply_filters( "edit_{$post_type}_per_page", $posts_per_page );

Where the hook is used (in WP core)

Does not used.