Table JOIN and CREATE new table extremely slow
You are doing DDL along with the SELECT

Doing CREATE TABLE AS SELECT mechanically does two commands


CREATE TABLE
INSERT INTO ... SELECT


This will produce locks on both calls and planned

I have written about this behavior in some of my older posts


Mar 23, 2012 : MySQL Locks while CREATE TABLE AS SELECT
Aug 08, 2014 : MySQL consistent nonlocking reads vs. INSERT ... SELECT