Questions for discovery

• How to measure? JCR queries don't provide aggregation functions. Iterating of a result set or the items of the workspace might not be efficient and might add to much load to the instance. This is the same concern like for pages (MAGNOLIA-9207), however the number of sites should me much smaller.
• Can and should we track this number separately. Risk of getting out of sync?

Discovery

• This could be implemented by registering an MBean that exposes the number of sites reported from the SiteManager. (i.e. info.magnolia.module.site.SiteManager#getSites#size.