Refresh requests are received by a data source that each request a snapshot of current members of one of a plurality of dynamically changing groups and dynamically changing rules corresponding to such group. Thereafter, the data source queues the received plurality of refresh requests for selective execution or deletion into a new request queue. In addition, real-time execution of refresh jobs are initiated for all of queued refresh requests if a number of refresh requests in both of the new request queue and a waiting requests queue is below a pre-defined threshold. Alternatively, a job framework schedules execution of task jobs for a subset of the queued requests in the new request queue and the waiting requests queue if certain conditions are met.