- Companion:
- class
Value members
Concrete methods
Scala API: ShardAllocationStrategy that allocates new shards to the ShardRegion (node) with least
number of previously allocated shards.
Scala API: ShardAllocationStrategy that allocates new shards to the ShardRegion (node) with least
number of previously allocated shards.
When a node is added to the cluster the shards on the existing nodes will be rebalanced to the new node.
The LeastShardAllocationStrategy picks shards for rebalancing from the ShardRegions with most number
of previously allocated shards. They will then be allocated to the ShardRegion with least number of
previously allocated shards, i.e. new members in the cluster. The amount of shards to rebalance in each
round can be limited to make it progress slower since rebalancing too many shards at the same time could
result in additional load on the system. For example, causing many Event Sourced entites to be started
at the same time.
It will not rebalance when there is already an ongoing rebalance in progress.
- Value parameters:
- absoluteLimit
the maximum number of shards that will be rebalanced in one rebalance round
- relativeLimit
fraction (< 1.0) of total number of (known) shards that will be rebalanced in one rebalance round