H5Pset_shared_mesg_phase_change
(
hid_t fcpl_id
,
unsigned max_list
,
unsigned min_btree
)
H5Pset_shared_mesg_phase_change
sets threshold values
for storage of shared object header message indexes in a file.
These phase change thresholds determine the point at which the
index storage mechanism changes from a more compact list format
to a more performance-oriented B-tree format, and vice-versa.
By default, a shared object header message index is initially
stored as a compact list.
When the number of messages in an index exceeds the threshold
value of max_list
, storage switches to a B-tree for
improved performance.
If the number of messages subsequently falls below the
min_btree
threshold, the index will revert to the
list format.
If max_list
is set to 0
(zero),
shared object header message indexes in the file will be
created as B-trees and will never revert to lists.
fcpl_id
specifies the file creation property list.
hid_t fcpl_id
|
IN: File creation property list identifier |
unsigned max_list
|
IN: Threshold above which storage of a shared object header message index shifts from list to B-tree |
unsigned min_btree
|
IN: Threshold below which storage of a shared object header message index reverts to list format |
Release | C |
1.8.0 | Function introduced in this release. |