Uploaded image for project: 'Hadoop YARN'
  1. Hadoop YARN
  2. YARN-4059

Preemption should delay assignments back to the preempted queue

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Resolved
    • Major
    • Resolution: Won't Fix
    • None
    • None
    • None
    • None

    Description

      When preempting containers from a queue it can take a while for the other queues to fully consume the resources that were freed up, due to delays waiting for better locality, etc. Those delays can cause the resources to be assigned back to the preempted queue, and then the preemption cycle continues.

      We should consider adding a delay, either based on node heartbeat counts or time, to avoid granting containers to a queue that was recently preempted. The delay should be sufficient to cover the cycles of the preemption monitor, so we won't try to assign containers in-between preemption events for a queue.

      Worst-case scenario for assigning freed resources to other queues is when all the other queues want no locality. No locality means only one container is assigned per heartbeat, so we need to wait for the entire cluster heartbeating in times the number of containers that could run on a single node.

      So the "penalty time" for a queue should be the max of either the preemption monitor cycle time or the amount of time it takes to allocate the cluster with one container per heartbeat. Guessing this will be somewhere around 2 minutes.

      Attachments

        1. YARN-4059.2.patch
          15 kB
          Chang Li
        2. YARN-4059.3.patch
          15 kB
          Chang Li
        3. YARN-4059.patch
          15 kB
          Chang Li

        Activity

          People

            lichangleo Chang Li
            lichangleo Chang Li
            Votes:
            0 Vote for this issue
            Watchers:
            11 Start watching this issue

            Dates

              Created:
              Updated:
              Resolved: