Setting the scaling factor
The scaling factor determines the number of storage containers that Vertica uses to store each projection across the database during rebalancing when local segmentation is enabled. When setting the scaling factor, follow these guidelines:
-
The number of storage containers should be greater than or equal to the number of partitions multiplied by the number of local segments:
num-storage-containers
>= (
num-partitions
*
num-local-segments
) -
Set the scaling factor high enough so rebalance can transfer local segments to satisfy the skew threshold, but small enough so the number of storage containers does not result in too many ROS containers, and cause ROS pushback. The maximum number of ROS containers (by default 1024) is set by configuration parameter ContainersPerProjectionLimit.
Use the SET_SCALING_FACTOR function to change your database's scaling factor. The scaling factor can be an integer between 1 and 32.
=> SELECT SET_SCALING_FACTOR(12);
SET_SCALING_FACTOR
--------------------
SET
(1 row)