title: MySQL 5.7 default install running much slower than 5.6
body: <p>I have a java / spring / hibernate app running with connections to a MySQL db.</p>
  
  <p>We recently upgraded from 5.6 to 5.7 (on a Windows server) and the app has gone from taking 3 hours to 3 days to complete.  It essentially uses hibernate connections to retrieve read only data from the db before processing it and dumping the result elsewhere.</p>
  
  <p>However as a first step, partly to check it was the upgraded version that is causing the problem, I installed 5.7.21 on my dev machine.  I then noticed that even doing a db restore took several hours rather than what used to take about 10 minutes on 5.6.  This has lead me to believe it may be more of a config issue than 'drivers' being out of date (I did think my first step was going to be upgrading app dependencies).  I didn't install the server but I installed my dev machine with a default 'developer' install.  Both the server and the dev machine are 64 bit Windows.</p>
  
  <p>I've had a scoot around for obvious gotchas and not found anything yet.  I just wondered if anyone could point me in the right direction before I start seriously thrashing about ?  I have a good basic understanding of out of the box MySQL but I haven't done much config so even pointers to likely suspects in my.ini and best ways to investigate would be helpful.</p>