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h1. 1.0.0

h2. HA Cluster

The master/slave architecture of the cluster allows it to scale horizontally by introducing more workers and also ensures availability. We call the master 'Coordinator' and the slave nodes 'Workers'.

h3. Coordinator

* Load balances /extract requests
* Load balances dictionary updates
* Manages update feeds
* Manages worker dictionary queries

h3. Worker
* Keeps track of its dictionaries fingerprint
* Creates a pool of pipelines
* Serves extraction requests
* Ability to update it's Gazetteer and Metadata PR SPARQL queries
* Ability to reload the whole pipeline dictionary

h2. Dynamic updates

* Multiple retries on failed update, full dictionary reload is triggered after a limit is hit (configurable)
* EUF plug-in keeps track of updated entities and serves changelists through special SPARQL queries
* Updates are kept track of via GraphDB's fingerprints