H5P_SET_EST_LINK_INFO inserts two settings into the group creation property list
gcpl_id: the estimated number of links that are expected to be inserted into a group created with the property list and the estimated average length of those link names.
The estimated number of links is passed in
The estimated average length of the anticipated link names is passed in
The values for these two settings are multiplied to compute the initial local heap size (for old-style groups, if the local heap size hint is not set) or the initial object header size for (new-style compact groups; see Group implementations in HDF5). Accurately setting these parameters will help reduce wasted file space.
If a group is expected to have many links and to be stored in dense format, set
0 (zero) for maximum efficiency. This will prevent the group from being created in the compact format.
See Group implementations in HDF5 in the H5G API introduction for a discussion of the available types of HDF5 group structures.