Automatic De-fragmentation of Dynamic Database Objects

If a class contains dynamically extended components (i.e. fields of type string, vector, varbinary and sequence), an object of this class that is frequently updated can develop memory holes. To prevent this kind of fragmentation, an automatic de-fragmentation (auto_compact mode) feature is provided via a database parameter autocompact_threshold.

If the size of an object exceeds this autocompact_threshold value, then the automatic de-fragmentation algorithm reallocates objects, eliminating any internal fragmentation.