Sets estimated number of links and length of link names in a group
Procedure:
H5P_SET_EST_LINK_INFO ( gcpl_id, est_num_entries, est_name_len )
Signature:
herr_t H5Pset_est_link_info(
hid_t gcpl_id,
unsigned est_num_entries,
unsigned est_name_len
)
Fortran90 Interface: h5pset_est_link_info_f
SUBROUTINE h5pset_est_link_info_f(gcpl_id, est_num_entries, est_name_len, &
hdferr)
IMPLICIT NONE
INTEGER(HID_T), INTENT(IN) :: gcpl_id
! Group creation property list identifier
INTEGER, INTENT(IN) :: est_num_entries
! Estimated number of links to be
! inserted into group
INTEGER, INTENT(IN) :: est_name_len
! Estimated average length of link names
INTEGER, INTENT(OUT) :: hdferr ! Error code
! 0 on success and -1 on failure
END SUBROUTINE H5Pset_est_link_info_f
Parameters:
hid_t gcpl_id | IN: Group creation property list identifier |
unsigned est_num_entries | IN: Estimated number of links to be inserted into group |
unsigned est_name_len | IN: Estimated average length of link names |
Description:
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 est_num_entries. The limit for est_num_entries is 64 K.
The estimated average length of the anticipated link names is passed in est_name_len. The limit for est_name_len is 64 K.
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 est_num_entries to 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.
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Example:
History:
| Release | Change |
|---|
| 1.8.0 | Function introduced in this release. |
--- Last Modified: November 15, 2019 | 10:30 AM
