class type bm_view_t =View on blockmap state:object..end
method blockmap_get_e : identity:string -> Nn_blockmap.blockmap_t Uq_engines.engineblockalloc table for this datastore
        identity, wrapped into a blockmap_t objectmethod blockmap_alloc_e : inode:int64 ->
       rpolicy:Nn_alloc_types.rpolicy ->
       index:int64 ->
       number:int ->
       pref:string list ->
       Nn_alloc_types.transacted_datastores ->
       Nn_blockmap.reserve_info -> Nn_blocklist.blocklist Uq_engines.engineindex is the first
        index number to use in the returned list of blocks, index+number-1
        is the last index number. For each index blocks are allocated on
        the datanodes according to rpolicy (usually with replicas).
        At reservation time, only the blockmap is updated; at commit time
        the blockalloc database table. The blocks are not associated with
        inodes yet.
	pref: list of preferred datanodes, given as identity strings.
	reserve_info: gives hints where to allocate blocks
method blockmap_allocsize : intmethod blockmap_dealloc_e : inode:int64 -> (string * int64 * int64) list -> unit Uq_engines.engine(identity,block,number).method blockmap_load_e : unit -> unit Uq_engines.enginemethod blockmap_keep : inode:int64 -> (string * int64 * int64) list -> unitblockmap_load_e).