Default resource allocation policy

When a consumer experiences demand, EGO considers resources from each of these five areas, and systematically allocates them (by default) in this order according to the configured resource plan:
  1. Idle resources already owned by the consumer

  2. Idle, unowned resources from the share pool
    1. Unowned resources within a particular branch in the consumer tree

    2. Unowned resources from other branches in the consumer tree, eventually moving up the tree to distribute any unowned resources from the cluster level

  3. Idle resources owned by other consumers that are configured for lending (borrowed resources)

  4. Resources owned by the consumer but currently lent-out to other consumers (reclaimed resources to owner)

  5. Unowned resources from the share-pool but currently in use by consumers with a smaller share-ratio (reclaimed resources to share-pool)

You can change the default resource allocation policy so that owned resources get reclaimed by consumers before they are borrowed or allocated from elsewhere . You can also adjust the allocation policy so that resources are never reclaimed by the share pool, but are only returned when the borrowing client releases them.

The following table illustrates the revised order of resource allocation depending on configured policy changes.

Default allocation order

Changed policy: Reclaim before borrow

Changed policy: No reclaim on share pool

Idle resources owned by consumer

Idle resources owned by consumer

Idle resources owned by consumer

Idle, unowned resources from share pool

Idle, unowned resources from share pool

Idle, unowned resources from share pool

Idle resources borrowed from other consumers

Resources reclaimed by consumer

Idle resources borrowed from other consumers

Resources reclaimed by consumer

Resources reclaimed by share pool from over-allocated consumers and then re-allocated to deserving consumers with a higher-share ratio

Resources reclaimed by consumer

Resources reclaimed by share pool from over-allocated consumers and then re-allocated to deserving consumers with a higher-share ratio

Idle resources borrowed from other consumers