Tasks
Data caching
Data caching is used to minimize the back-end database calls while at the same time assuring the currency of the data. In most cases, the decision for data currency is a business decision. There are multiple methods for configuring data caching:
Keep a local copy in a database within the same network realm as the app.
Cache data from a localized database in memory to minimize database reads.
Use EJB persistence to keep the data in the memory space of the running app.
Sometimes data is provided by an external provider. Making live calls to this data can prove to be a single point of failure and a slower performer. If there are no strict dependencies on the currency of the data, offloading this data, or a subset, to a local database can provide large performance, availability, and scalability gains. The data can be refreshed periodically, preferably during off-peak hours for the app.