Comments can be extremely valuable for anyone who has to review, maintain, or troubleshoot your code. This includes future you. I highly recommend against worrying about the performance impact of a reasonable amount of comments, and instead focus on prioritizing the usefulness of context that the comments provide. As someone on Twitter said, there is a limit. If your comments amount to the abridged version of War and Peace, you might consider – at the risk of decoupling the code from its documentation – putting that documentation elsewhere, and reference the link in the procedure body comments.