Description of state that can be persistent
A correlator that is running with persistence enabled automatically stores state on disk and automatically recovers state when it restarts. Saved state includes the following:
For a persistent EPL monitor, all of that monitor's state is saved. This includes all events, strings, primitives, sequences, dictionaries, action variables, closures, and global variables. It also includes all the state of listeners and streams — local variables captured by them and all active listeners and sublisteners, including the events currently flowing through them.
All source code that was injected into the correlator, including any non-persistent EPL monitors. EPL files that were injected from a correlator deployment package (CDP) are not stored in plain text.
Code that is not injected includes the following:
EPL plug-ins, which are imported at runtime. The actual plug-in file must be on a specified path that the correlator can load it from.
Any Java class files on the correlator's classpath but not injected.
The correlator runtime itself.
Contents of all context queues.
Some correlator-global state including
integer.getUnique() and
integer.incrementCounter() IDs and context IDs. See the
API Reference for EPL (ApamaDoc) for more information on the
integer type and its built-in methods
incrementCounter and
getUnique.
Note:
In general, chunks cannot be persistent. However, chunks used by the Apama Time Format plug-in and the Apama MemoryStore plug-in can be persistent.