# Mysterious one point rep increase

Yesterday my reputation total increased by 1 point. As far as I know there is (was) no action which would trigger 1 point increase (downvoting gives $-1$, accepting an answer gives $+2$, etc.) I am curious what was the cause of a 1-point increase. Does anybody know?

• Maybe a post you downvoted was deleted. – Michael Greinecker Jun 26 '13 at 9:28
• @Michael: I have not downvoted a post for at least a year. But indeed perhaps one of the old posts was deleted. – user6976 Jun 26 '13 at 9:31
• I know what happened here looking at the data...once I'm at a computer I'll give a full write up. The basics a are it's a delayed recalc to ensure rep is correct when a rare race occurs on real time updates...will give a full explanation in a bit. I can't give specific examples without saying specifically which post you downvoted (I think, need to see) would you want me to do this, and give the concrete example of what happened in this exact case? – Nick Craver ModStaff Jun 26 '13 at 10:16
• @Nick: I tried to look at recently deleted posts and could not find it. But if you have time and can find the post, it would be nice. – user6976 Jun 26 '13 at 10:18

Undownvoting or the deletion of a downvoted post. There ought to be a "show removed posts" checkbox at the bottom of your reputation history that will display this.

You can also audit your reputation from here (though this is considerably more confusing)

• Thank you, but I could not find the deleted post. Perhaps a better way is to use the "review" and see posts that are recently deleted. – user6976 Jun 26 '13 at 9:42
• It is strange but among recently deleted posts there are none which I downvoted. – user6976 Jun 26 '13 at 10:01

This is an artifact of the recalc process that runs every night. To see what happens, let's take the simple 2 request case. These are happening in Parallel:

|(Start)----(Get your Rep: 10)------(Add 10 rep from upvote)-----(Save Rep=20 to DB)|

The key here is that when the save happens, the database update is = in Linq2SQL (one reason we're slowly removing it and not using it for new things), it's not += or -= which would solve the problem. To be technically accurate, it would greatly narrow the scope of it by narrowing the race window due to our READ UNCOMMITTED transaction isolation level, not 100% solve it.