Comment 1 for bug 2061166

I think you've hit the nail on the head with:

"it looks like some unit is executing every time sunbeam checks the status."

Sunbeam uses the libjuju wait_for_idle method to determine when a particular state has been reached - this includes a list of applications for which all units must be in the 'active' state but also that the agents must all be idle - which means no hooks executing.

When the number of units increases, the probability of the check always seeing something executing also increases (think update-status which runs every 5 mins, but across many units this could be *allthetime* somewhere in the model).

My gut feel is to not check for the idle agent status, and just rely on the units and the charm code supporting them knowing when active really means active.