> A few applications hit repeatable-read transaction deadlocks involving insert … on duplicate key queries on InnoDB. 5.6 had a bug which was corrected in 8.0,

> A few applications hit repeatable-read transaction deadlocks involving insert … on duplicate key queries on InnoDB. 5.6 had a bug which was corrected in 8.0, but the fix increased the likelihood of transaction deadlocks. Interesting, I've run into a bug in MySQL 5.6 involving select for update where it deadlocked when it shouldn't. I wonder if the two were related.