Enable host scavenging

Platform Symphony must be installed and running.

  1. On each host that you want to scavenge, run egoconfig addresourceattr "[resource scvg]".

    Adds "scvg" resource tag to hosts to indicate they are scavenge-ready.

  2. Restart the hosts you added the resource tag to.
  3. From any host, run egosh ego elimrestart SA on host_name ....
    Sets the agent control flag to "on" and enables the scavenging agent on the specified hosts. The following default threshold values are used:
    • Idle time threshold in minutes: 10

    • CPU utilization threshold as a percentage: 0

    • CPU idle time threshold in minutes: 10

    The thresholds are configurable.

    Note:

    The remaining steps are optional, but recommended.

  4. From the Platform Management Console, create a new dynamic resource group for scavenge-ready hosts.
    1. Name the group in such a way that you can identify it as a group of scavenge-ready hosts.
    2. Select Hosts filtered by resource requirement and in the resource requirement, specify: select (!mg && scvg)
    Note:

    Create this resource group after all other resource groups have been created. This ensures that the dedicated grid resources are used before the scavenge-ready resources. Work is only allocated to your scavenge-ready resources if all other resources are busy. Note that this principle only applies if you complete the remaining steps and no other resource groups are added after the scavenge group.

    The resource group dynamically includes any host that is not a management host and has the "scvg" resource tag associated with it.

  5. In all other resource groups that use compute hosts, add
    !scvg
    to the resource requirement.

    This prevents host overlaps between resource groups.

  6. From the Platform Management Console, identify the applications that you want to have work running on scavenged hosts.
    1. Modify the consumer properties to include the new scavenge resource group for each application that should run on scavenged hosts.
    2. Check that the grace period specified is appropriate. Work is terminated on a scavenged host when it becomes busy, taking the grace period into consideration. A lower grace period terminates the work faster than a higher grace period.
    Note:

    Specify any number of resource groups in addition to the scavenge resource group if you want the work to run on dedicated cluster hosts as well. Work only runs on scavenged hosts if dedicated hosts are not available. Again, this principle is only true if you complete the optional steps in this procedure.

  7. Create a new consumer and name it so you can identify that it is used only for scavenging.
    1. Specify the new scavenge resource group as the consumer’s only resource group.

    This consumer owns all the slots of the scavenge-ready resource group and lends them to other consumers as needed.

    Note:

    Never register any applications to this consumer.

  8. Modify the resource plan for the scavenge resource group.
    1. Specify the scavenge consumer to own all slots that will be scavenged.

      You can set the scavenge consumer to own more slots than are displayed if you know more scavenge-ready host slots will be available in the future.

    2. Enable lending but specify no limit.
    3. Leave borrowing disabled.
    4. Disable sharing.

      This introduces a non-editable default setting.

  9. Enable borrowing in the resource plan for the consumers associated with applications that you want to make use of scavenge-ready hosts.