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Wondering if there is something misconfigured in my devstack
environment, which was reinstalled on RHEL7 about 10 days ago.
I'm often running into mysql connections problem as shown below:

$ mysql
ERROR 1040 (HY000): Too many connections

When I try dump the mysql connection list, I'm getting the followng
result after a 'systemctl restart mariadb.service':

$ mysqladmin processlist | grep nova | wc -l
125

Most of the connections are at Sleep status:

$ mysqladmin processlist | grep nova | grep Sleep | wc -l
123

As for the workload, I'm currently only running two VMs in a multi-host
devstack environment.

So, my questions:

  - Why do we have so many mysql connections from nova?
  - Is it possible this is caused some misconfigurations?
  - 125 connections in such a toy setup is insane, any hints on nailing
    down the connections to the responsible nova components?

Thanks.

Regards,
  Qiming