GemFire sharding

When describing the Persistence layer earlier, we listed the new components related to Persistence in vRealize Operations 6.6, Now it's time to discuss what sharding actually is.

GemFire sharding is the process of splitting data across multiple GemFire nodes for placement in various partitioned buckets. It is this concept in conjunction with the controller and locator services that balance the incoming resources and metrics across multiple nodes in the vRealize Operations Cluster. It is important to note that data is sharded per resource, and not per adapter instance. For example, this allows the load balancing of incoming and outgoing data, even if only one adapter instance is configured. From a design perspective, a single vRealize Operations cluster could then manage a maximum configuration vCenter by distributing the incoming metrics across multiple data nodes.

vRealize Operations data is sharded in both the Analytics and Persistence layers, which is referred to as GemFire cache sharding and GemFire Persistence sharding respectively.

Just because data is held in the GemFire cache on one node, this does not necessarily result in the data shard persisting on the same node. In fact, as both layers are balanced independently, the chance of both the cache shard and Persistence shard existing on the same node is 1/N, where N is the number of nodes.