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2.20 Set HDF5 Chunk Cache for Future File Opens/Creates: NF_SET_CHUNK_CACHE

This function changes the chunk cache settings in the HDF5 library. The settings apply for subsequent file opens/creates. This function does not change the chunk cache settings of already open files.

This affects the per-file chunk cache which the HDF5 layer maintains. The chunk cache size can be tuned for better performance.

For more information, see the documentation for the H5Pset_cache() function in the HDF5 library at the HDF5 website: http://hdfgroup.org/HDF5/.

Usage

     INTEGER NF_SET_CHUNK_CACHE(INTEGER SIZE, INTEGER NELEMS, INTEGER PREEMPTION);
SIZE
The total size of the raw data chunk cache in MegaBytes.
NELEMS
The number slots in the per-variable chunk cache (should be a prime number larger than the number of chunks in the cache).
PREEMPTION
The preemtion value must be between 0 and 100 inclusive and indicates how much chunks that have been fully read are favored for preemption. A value of zero means fully read chunks are treated no differently than other chunks (the preemption is strictly LRU) while a value of 100 means fully read chunks are always preempted before other chunks.

Return Codes

NF_NOERR
No error.
NF_EINVAL
Parameters size and nelems must be non-zero positive integers, and preemption must be between zero and 100 (inclusive). An NF_EINVAL will be returned otherwise.