See https://github.com/ooici/coi-services/blob/master/ion/agents/platform/platform_resource_monitor.py#L65 for how the attrs are grouped: essentially, it groups the attrs by "similar" poll rate so a single greenlet is launched for each group. "similarity" is given by a group size in seconds, so attributes having poll rates differing by at most that group size will go to the same group.

The publish rate is set to be the minimum of the polling rates.