...
WSO2 Identity Server is using Infinispan Hazelcast for underlying caching implementation to distribute the policy cache among clustered Identity Servers. Therefore communication between the cluster nodes is handled by the JGroups.
Attribute Cache
- Attribute cache or cache entry must be updated (invalidated), when external attribute sources are updated.
- Cache or cache entry updating (invalidating) messages must be distributed among clustered PDPs
...
WSO2 Identity Server provides set of APIs to invalidate the attribute cache or cache entries whenever external attribute sources are updated. Attribute Cache is distributed among cluster nodes using Infinispan Hazelcast caching implementation. Therefore we do not want to worry about the The distribution of cache invalidation messages among cluster nodes is done very efficiently.
Decision Cache
- PDP Decision cache must be invalidated, when policy cache updated, attribute cache is invalidated and global policy combining algorithm is updated.
- Cache invalidation messages must be distributed among clustered PDPs
WSO2 Identity Server provides a concurrent hash map based caching implementation as the decision cache. Cache is not distributed among cluster nodes. Only the cache invalidation messages are distributing by using the same Infinispan Hazelcast caching implementation. Therefore if the cache is invalidated in one node, all decision caches in other nodes are also invalidated. Also there is some invalidation time interval for each cache entry (Decision). The time out value can be configurable and this would lead a solution for cache growth.
...