About Restartability and Persistence
Ehcache offers persistence using the local disk as a cache storage tier. While Ehcache offers various disk usage choices, as of version 2.6, the recommended option for persistence is the Fast Restart store, which is available in BigMemory Go and BigMemory Max. Open-source Ehcache offers a limited version of persistence, as noted in this document.
The Fast Restart feature provides enterprise-ready crash resilience with an option to store a fully consistent copy of the cache on the local disk at all times. The persistent storage of the cache on disk means that after any kind of shutdown — planned or unplanned — the next time that the application starts up, all of the previously cached data is still available and very quickly accessible.
The advantages of the Fast Restart store include:
A persistent store of the cache on disk survives crashes, providing the fastest restart. Because cached data does not need to be reloaded from the data source after a crash, but is instead loaded from the local disk, applications can resume at full speed after restart. Recovery of even terabytes of data after a failure will be very fast, minimizing downtime.
A persistent store on disk always contains a real-time copy of the cache, providing true fault tolerance. Even with BigMemory, where terabytes of data can be held in memory, the synchronous backup of data to disk provides the equivalent of a hot mirror right at the application and server nodes.
A consistent copy of the cache on local disk provides many possibilities for business requirements, such as working with different datasets according to time-based needs or moving datasets around to different locations. It can range from a simple key-value persistence mechanism with fast read performance, to an operational store with in-memory speeds during operation for both reads and writes.
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