WebSphere eXtreme Scale - Basic Components

Map -
A map is a container for key-value pairs, which allows an application to store a value indexed by a key. A map set is a collection of maps with a common partitioning algorithm. A map set can have a schema associated with it. A schema is the metadata that describes the relationships between each map when using homogeneous Object types or entities.

Container Server -

"The container server stores application data for the data grid. This data is generally broken into parts, which are called partitions, which are hosted across multiple container servers. Each container server in turn hosts a subset of the complete data. A JVM might host one or more container servers and each container server can host multiple shards." - IBM Documentation

Parition -

"Partitions host a subset of the data in the grid. WebSphere eXtreme Scale automatically places multiple partitions in a single container server and spreads the partitions out as more container servers become available." - IBM Documentation

Shards -

Shards are instances of partitions and have one of two roles: primary or replica. The primary shard and its replicas make up the physical manifestation of the partition.

Clients -

Clients connect to a catalog service, retrieve a description of the server topology, and communicate directly to each server as needed. This is the application that uses the WXS data and services.


Catalog service -

Locatin service - "traffic cop" - "google map" guidance for traffic from client to container and from container to client

Placement service - "The placement service is the central nervous system for the grid and is responsible for allocating individual shards to their host container." - IBM Documentation


Core Group Management -
This is the same as WAS core group - the manager manages peer grouping for health onitoring, organizes containers into small groups of servers, and automatically federates the groups of servers.