A storage system includes a storage medium containing blocks identified by
block addresses. The storage medium stores hierarchical data structures,
each hierarchical data structure containing plural levels of data
objects. Each hierarchical data structure is stored in a respective group
of blocks. In response to a request containing an identifier of at least
one of the hierarchical data structures, a controller generates one or
more block addresses based on the identifier. The controller accesses one
or more blocks indicated by the one or more block addresses.