DataDog/dd-agent — pull request #671 by jslatts (2013-09-13 16:57:20+00:00)
Title: Add a query for checking replication slave status via Slave_running variable

I am currently using this to graph and alert on slave status. This variable should be reliable enough on more recent versions of mysql to ascertain slave status.

I looked into grabbing Slave_IO_Running and Slave_SQL_Running, but the show slave status command does not allow isolation of those variables so we would have to manipulate the text post query which would have been a deeper change.

This also might help address issue #425