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["Davanum Srinivas \(DIMS\)" <davanum@xxxxxxxxx>]

** Also affects: oslo.db
   Importance: Undecided
       Status: New

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https://bugs.launchpad.net/bugs/1007027

Title:
  Unnecessary "SELECT 1" statements spamming MySQL server

Status in OpenStack Compute (Nova):
  Confirmed
Status in Oslo Database library:
  New

Bug description:
  Nova is issuing a lot of unnecessary "SELECT 1" queries against its
  MySQL database. I believe this is due to the MySQLPingListener()
  function in nova/db/sqlalchemy/session.py.

  Even though "SELECT 1" is a light-weight database call, it is
  unnecessary and wasting resources (database CPU cycles) and time
  (extra network round trips), and is not guaranteeing a valid database
  connection. In other words, it is just a waste of resources.

  See http://www.mysqlperformanceblog.com/2010/05/05/checking-for-a
  -live-database-connection-considered-harmful/ for a longer discussion
  of why this should be removed.

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