Are parallel queries with mysqlnd actually possible? So I have been playing with asynchronous database requests in PHP using mysqlnd in an attempt to achieve parallel database requests and cut down total execution time i.e. rather than:

total time = query 1 time + query 2 time + query 3 time + query 4 time


instead:

total time = max(query 1 time, query 2 time, query 3 time, query 4 time)


My thinking is that using MYSQLI_ASYNC makes the query non blocking allowing you to kick of a number of queries right after another with a new connection, and as MySQL handles queries in parallel natively, thus achieve execution of parallel database requests.  I am however seeing absolutely no improvement in execution time whatsoever and instead am seeing the same execution time as if the queries are run one after the other.

Where am I going wrong and is this actually possible?  (note I am a developer not a sysadmin)
Recommend you work on speeding up each query. Parallel execution in PHP, especially on Windows, is mostly a myth. 

Better evidence