Between Backing Store and Cache Preloading Options and Limited Cache Size

Best performance is obtained when all objects are in the cache, but in practice there are often more objects than you can or want to keep in the cache.

When the system demands an object that exists in backing store but not in cache, the object is automatically loaded from the backing store into the cache, and then into the Rete network. This takes time, but reduces the need to store so much data in the cache, which uses up memory.

You can configure what objects to preload into cache on startup, and what objects to evict from the cache when not needed. You can preload all, none, or entities of selected types. You can also configure what object handles to preload into the object table. Again, you can preload handles for all, none, or selected types. The first RTC does not occur until the object table has been preloaded (with all the object handles configured for preloading). For more details, see The Role of the Object Table.

It is also important to start enough cache agents to handle the work.

Limiting Cache Size

When you use a backing store, you can limit the size of the cache by specifying the cache size. This is helpful for large volumes of data that the available memory cannot hold. When the number of objects in cache reaches the cache size limit, some of the objects are automatically evicted from cache (they are still in the backing store).

See Cache OM and Cluster Configuration in TIBCO BusinessEvents Configuration Guide.