tuning feature only: reserves a number of bytes in database files.
tuning feature only: reserves a number of bytes in database files.
The global setting is used for the creation of new database files. Continous calls on an ObjectContainer Configuration context (see com.db4o.ext.ExtObjectContainer.Configure ) will continually allocate space.
The allocation of a fixed number of bytes at one time makes it more likely that the database will be stored in one chunk on the mass storage. Less read/write head movevement can result in improved performance.
Note:
Allocated space will be lost on abnormal termination of the database engine (hardware crash, VM crash). A Defragment run will recover the lost space. For the best possible performance, this method should be called before the Defragment run to configure the allocation of storage space to be slightly greater than the anticipated database file size.
Default configuration: 0
Configuration Interface | com.db4o.config Namespace