Don't stop mysql if temp tables exists

[Steve Caldwell]

We've been having trouble when running the script with the --mysql-stop command against a slave database. What happens is that the script will shutdown mysql while the slave has temporary tables in memory, the tables are lost, and then the slave will not start correctly on either the host machine or from the snapshot.

See:
http://dev.mysql.com/doc/refman/5.1/en/replication-features-temptables.html

A fix for this would be to have ec2-consistent-snapshot perform the procedure listed on that url, namely to stop the slave sql thread, check if any temp tables exist, and abandon if so. ec2-consistent-snapshot could retry multiple times, and then refuse to stop mysql if it can't get to a state without temp tables.

[Eric Hammond (esh)]

Thank you for submitting this report. I love the idea. If you or somebody on your team would like to submit a patch for this behavior, I will gladly review it for merging.

[Steve Caldwell (scaldwell)]

Eric: we'll work on that.