realname_make_name updating DB for every comment shown on a node

Apologies if this is a duplicate issue, but I haven't had luck looking for an answer to my problem...

I have noticed that realname_make_name gets called many times when viewing nodes, and it is updating the DB every time. This is rather annoying and potentially slowing my website down significantly. I have narrowed it down to the comments on a post; for every comment shown, a link to the user is shown with the user's "Real Name."

Is there any way that I can prevent all these updates happening every time a node is viewed, but still show the "real name" of the comments' author?

thanks for any help in this matter!