These tables summarize the library's fill value writing behavior for various property list settings and compare serial I/O vs. parallel I/O.

Serial I/O

Allocation time default settings are dependent on the dataset storage method:

Dataset Storage Method

Contiguous Chunked Compact

Allocation Time Early Incremental Late

Fill Value default is "Library Default" (all zero bytes for datatype).

Fill Time default is "If Set".

Serial I/O results
			Dataset Storage Method
Fill Value	Fill Time	Allocation Time	Contiguous	Chunked	Compact
Library Default*	Never	Early	No Fill Value Written	No Fill Value Written	No Fill Value Written
		Incremental	Same as Late	No Fill Value Written	Error
		Late	No Fill Value Written	No Fill Value Written	Error
	If Set*	Early	No Fill Value Written	No Fill Value Written	No Fill Value Written*
		Incremental	Same as Late	No Fill Value Written*	Error
		Late	No Fill Value Written*	No Fill Value Written	Error
	Allocation	Early	Library Fill Value Written During Creation	Library Fill Value Written To All Chunks During Create	Library Fill Value Written During Creation
		Incremental	Same as Late	Library Fill Value Set In Each Chunk Accessed During Write	Error
		Late	Library Fill Value Written During Write	Library Fill Value Written To All Chunks During Write	Error
User-defined	Never	Early	No Fill Value Written	No Fill Value Written	No Fill Value Written
		Incremental	Same as Late	No Fill Value Written	Error
		Late	No Fill Value Written	No Fill Value Written	Error
	If Set*	Early	User Fill Value Written During Creation	User Fill Value Written To All Chunks During Create	User Fill Value Written During Creation*
		Incremental	Same as Late	User Fill Value Set In Each Chunk Accessed During Write*	Error
		Late	User Fill Value Written During Write*	User Fill Value Written To All Chunks During Write	Error
	Allocation	Early	User Fill Value Written During Creation	User Fill Value Written To All Chunks During Create	User Fill Value Written During Creation
		Incremental	Same as Late	User Fill Value Set In Each Chunk Accessed During Write	Error
		Late	User Fill Value Written During Write	User Fill Value Written To All Chunks During Write	Error
Undefined	Never	Early	No Fill Value Written	No Fill Value Written	No Fill Value Written
		Incremental	Same as Late	No Fill Value Written	Error
		Late	No Fill Value Written	No Fill Value Written	Error
	If Set*	Early	No Fill Value Written	No Fill Value Written	No Fill Value Written*
		Incremental	Same as Late	No Fill Value Written*	Error
		Late	No Fill Value Written*	No Fill Value Written	Error
	Allocation	Early	Error	Error	Error
		Incremental	Same as Late	Error	Error
		Late	Error	Error	Error

* - Default setting.

Parallel I/O

For parallel I/O, the allocation time setting in the dataset creation property list is ignored and H5D_ALLOC_TIME_EARLY is used for all dataset creation calls. The fill value and fill time default settings are the same as for serial I/O.

Parallel I/O results
		Dataset Storage Method
Fill Value	Fill Time	Contiguous	Chunked	Compact
Library Default*	Never	No Fill Value Written	No Fill Value Written	No Fill Value Written
	If Set*	No Fill Value Written	No Fill Value Written	No Fill Value Written
	Allocation	Library Fill Value Written During Creation	Library Fill Value Written To All Chunks During Create	Library Fill Value Written During Creation
User-defined	Never	No Fill Value Written	No Fill Value Written	No Fill Value Written
	If Set*	User Fill Value Written During Creation	User Fill Value Written To All Chunks During Create	User Fill Value Written During Creation
	Allocation	User Fill Value Written During Creation	User Fill Value Written To All Chunks During Create	User Fill Value Written During Creation
Undefined	Never	No Fill Value Written	No Fill Value Written	No Fill Value Written
	If Set*	No Fill Value Written	No Fill Value Written	No Fill Value Written
	Allocation	Error	Error	Error