Defining global rules for cluster workload placement

A multicluster administrator, or a user with the required permissions, defines a set of global (default) rules for workload placement. This includes determining criteria to fill clusters with workload, and selecting a ranking method for filling the clusters. You can also enable cluster bursting at the global level.

1. From the multicluster management console, click System > Multicluster Settings > Workload Placement.
2. Expand the sub-section of the Global Workload Placement page.
3. Under the Assign workload to clusters until they are filled based on any of the following settings heading, select the criteria that governs how workload should be placed (filled) in all clusters participating in workload placement. Note that you can select multiple options; the system will combine these options with AND logic.

   Option	Description
   The application's active task to deserved slot ratio in the cluster is greater than number_of_active_tasks:1.	Select this option if you want to fill clusters with workload until the application's active (pending and running) tasks to deserved slot ratio in the cluster is greater than a specific ratio (for example, greater than a 10:1 ratio). Click number_of_active_tasks to specify the number of tasks.
   The cluster's active task to allocated slot ratio is greater than number_of_active_tasks:1.	Select this option if you want to fill clusters with workload until the cluster's active (pending and running) task to allocated slot ratio is greater than a specific ratio (for example, greater than a 10:1 ratio). Click number_of_active_tasks to specify the number of tasks.
   The application's active tasks in the cluster will take longer than number_of_seconds seconds to complete.	Select this option if you want to fill clusters with workload until the application's active tasks in the cluster will take longer than a specific amount of time, in seconds, to complete (for example, longer than 600 seconds). Click number_of_seconds to specify the maximum amount of time in seconds.
   The application's number of blocked hosts in the cluster is greater than number_of_blocked_hosts.	Select this option if you want to fill clusters with workload until the application's number of blocked hosts is greater than a specific number of hosts (for example, greater than 50 hosts). Click number_of_blocked_hosts to specify the maximum number of hosts.
   The application's number of pending tasks in the cluster is greater than number_of_pending_tasks.	Select this option if you want to fill clusters with workload until the application's number of pending tasks is greater than a specific number of tasks (for example, greater than 100 tasks). Click number_of_pending_tasks to specify the number of tasks.

4. Under the Order (rank) the filling of the clusters based on the following method (clusters that are considered full are ignored) heading, select a ranking method for filling the clusters:

   Option	Description
   By clusters with the earliest completion time	Select this option if you want to always fill the clusters based on the cluster with the earliest completion time for the application.
   By round-robin (per application)	Select this option if you want to always fill the clusters based on each application taking turns to fill the cluster.
   By a custom ranking of preference	Select this option if you want to always fill the clusters based on the available cluster closest to the beginning of a list of ranked clusters. Click Custom ranking of preference to see a list of clusters to rank: Select and drag the cluster to move it up or down the list, so that the cluster first on your list is ranked as your preferred cluster. The cluster you move to the end of the list is your least preferred cluster. Click Done to save the custom ranking. You can hover over the "i" icon next to By a custom ranking of preference to see the list of ranked clusters.

5. When clusters are filled with workload and you require more resources, you can use reserve clusters to accommodate the workload overflow. The reserved clusters are a secondary group of clusters after the primary group is filled with workload.
   1. Select Reserve cluster if you want to select clusters from your primary list of clusters to be in a secondary list of clusters used for the workload overflow.
   2. Click secondary group of clusters to see a list of clusters to identify for the secondary list.
   3. Select the clusters that you want to move from the primary list to the secondary list.
   4. Click Done.

      These secondary clusters will also use the fill criteria you specified in the Assign workload to clusters until they are filled based on any of the following settings section.

      You can hover over "i" icon next to secondary group of clusters to see the list of secondary clusters.

      If you hover over the "i" icon next to By a custom ranking of preference, you can see that clusters have moved from the primary list to a secondary list.

   5. Click Apply.