diff options
Diffstat (limited to 'release_docs')
| -rw-r--r-- | release_docs/RELEASE.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/release_docs/RELEASE.txt b/release_docs/RELEASE.txt index addd9b0..05daa53 100644 --- a/release_docs/RELEASE.txt +++ b/release_docs/RELEASE.txt @@ -151,6 +151,31 @@ New Features (DER - 2018/10/26, HDFFV-10614) + - Add ability to minimze dataset object headers. + + Creation of many, very small datasets resulted in extensive file bloat + due to extra space in the dataset object headers -- this space is + allocated by default to allow for the insertion of a small number of + attributes within the object header and not require a continuation + block, an unnecessary provision in the target use case. + + Inform the library to expect no attributes on created datasets, and to + allocate the least space possible for the object headers. + NOTE: A continuation block is created if attributes are added to a + 'minimized' dataset, which can reduce performance. + NOTE: Some extra space is allocated for attributes essential to the + correct behavior of the object header (store creation times, e.g.). This + does not violate the design principle, as the space is calculated and + allocated as needed at the time of dataset object header creation -- + unused space is not generated. + New API calls: + H5Fget_dset_no_attrs_hint + H5Fset_dset_no_attrs_hint + H5Pget_dset_no_attrs_hint + H5Pset_dset_no_attrs_hint + + (JOS - 2019/01/04, TRILAB-45) + Parallel Library: ----------------- |