There are several properties that can be adjusted by the administrator in order to tune the server. A complete list of supported properties is displayed when calling the ozoneInst tool without a parameter. Properties can be specified when calling the ozoneInst tool or when starting the server. Heap size of the VM ozone uses 32MB heap size by default. The heap size defines the size of the object cache of the server.
All available memory is used for the object cache.
The effect is comparable to OS page swapping. A related problem is the size of the central b-tree that object IDs into objects. Since the performance of this b-tree is very important for the entire ozone performance there are two cache levels for it. The first level is a small direct mapped cache. The second level caches the LRU pages of the b-tree in memory.