Is it possible to get a deadlock if you ran mysqldump with the argument --single-transaction ? or any other complication ?
If it is used to backup a live site with many other querys running at the same time.
The mysqldump process could take over few minutes to complete.
The tables are innodb.
I am concerned about the deadlocks errors that could happen on the live applications relying on the database during the time where mysqldump is running.