It is easy enough to understand the function of the statistics retnetion settings for APM, but I don't quite understand what the Polling Engine Mode is for.
Does it have to do with how APM data retention?
Polling Engine mode is only relevant if you have multiple polling engines. In that case, you can have the polling engines associated with the NPM polling engine or load-balanced.
As it pertains to data retention policies? What do you mean by associated with the main poller?
There's a good explanation of how this setting works in the Admin Guide
www.solarwinds.com/.../wwhelp.htm
