InnoDB auto-inc scalability fixed
There was long played scalability issue with InnoDB auto-increment field. In short words the problem is in case of insert into table with auto-increment column the special AUTO_INC table level lock is obtained, instead of usual row-level locks. With many concurrent inserted threads this causes serious scalability problems.
This is more a note to myself, as this results in some nasty performance deterioration and pretty much renders autoincrement fields in InnoDB useless for high traffic websites.