There's a bunch of notifiable_posts in the DB that were migrated from the old DB structure but pre-date the 1 year existence cap and don't have any attached context. The deletion mechanism works by looking for unused context and then deleting related posts, so it never catches these orphaned posts. They need to be cleaned up.
The orphaned posts account for something like 55% of post table row reads, so it's a significant amount of work that gets wasted on them.
There's a bunch of notifiable_posts in the DB that were migrated from the old DB structure but pre-date the 1 year existence cap and don't have any attached context. The deletion mechanism works by looking for unused context and then deleting related posts, so it never catches these orphaned posts. They need to be cleaned up.
The orphaned posts account for something like 55% of post table row reads, so it's a significant amount of work that gets wasted on them.