So I was recently asked to look into why the updated MySQL 5,.6 was slower than the older 5.5 

So I started by poking around looking over the standard variables and caches and etc.

The test case was a simple routine that took about twice as long to run on 5.6 than it did on 5.5. 

To add to the mix.. the 5.6 version had double the Innodb_buffer_pool_size and of course more ram overall.  

So I started some tests with MySQLslap...

Mysqlslap tests show it slower on 5.6 

5.6:
mysqlslap --defaults-file=./.my.cnf --concurrency=150 --iterations=130 -query=/test.sql --create-schema=applicationdata --verbose 
Benchmark
Average number of seconds to run all queries: 0.028 seconds
Minimum number of seconds to run all queries: 0.019 seconds
Maximum number of seconds to run all queries: 0.071 seconds
…