H5Pset_meta_block_size
(
hid_t fapl_id
,
hsize_t size
)
H5Pset_meta_block_size
sets the
minimum size, in bytes, of metadata block allocations when
H5FD_FEAT_AGGREGATE_METADATA
is set by a VFL driver.
Each raw metadata block is initially allocated to be of the given size. Specific metadata objects (e.g., object headers, local heaps, B-trees) are then sub-allocated from this block.
The default setting is 2048 bytes, meaning that the library
will attempt to aggregate metadata in at least 2K blocks in the file.
Setting the value to 0
(zero) with this function
will turn off metadata aggregation, even if the VFL driver attempts
to use the metadata aggregation strategy.
Metadata aggregation reduces the number of small data objects in the file that would otherwise be required for metadata. The aggregated block of metadata is usually written in a single write action and always in a contiguous block, potentially significantly improving library and application performance.
hid_t fapl_id |
IN: File access property list identifier. |
hsize_t size |
IN: Minimum size, in bytes, of metadata block allocations. |
SUBROUTINE h5pset_meta_block_size_f(plist_id, size, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: plist_id ! File access property list ! identifier INTEGER(HSIZE_T), INTENT(IN) :: size ! Metadata block size INTEGER, INTENT(OUT) :: hdferr ! Error code ! 0 on success and -1 on failure END SUBROUTINE h5pset_meta_block_size_f
Release | C |
1.4.0 | Function introduced in this release. |