Explain how JobTracker schedules a task?

Question

What is the task scheduling procedure of a JobTracker?

Answer 1

In Hadoop, the task of the task tracker is to send out heartbeat pings to the Jobtracker after a few minutes or so. This is done to ensure if the JobTracker is running and active. This heartbeat ping also conveys to the JobTracker the number of available slots. Based on the slot information, the JobTracker to appropriately schedule workload.