Description of problem:

During an Heat stack deletion, the stack failed and we are unable to remove it even after many retries.
We can see MySQL max_connection errors in the Heat logs:

   OperationalError: (_mysql_exceptions.OperationalError) (1040, 'Too many connections')\n"]."

The full log is in the "Additional info" section.

After raised the max_connections to 2048, I was able to delete the Heat stack.

Version-Release number of selected component (if applicable):

rhos-release-0.66-1.noarch
python-rdomanager-oscplugin-0.0.8-44.el7ost.noarch
puddle images 2015-07-30.1

How reproducible:

It can be reproduce with big Heat stack, like 10 nodes to deploy.

Steps to Reproduce:
1. Heat stack deployment
2. Heat stack deletion

Actual results:

Unable to delete the Heat stack even after many retries.

Expected results:

Be able to delete an Heat stack without error.

Additional info:

Heat error logs: http://pastebin.test.redhat.com/305355