From c84a46f49b5166af5b10b7d7b3341d8d1ab551ed Mon Sep 17 00:00:00 2001 From: Frank Baker Date: Fri, 5 Jul 2002 14:58:24 -0500 Subject: [svn-r5766] Purpose: Two new functions and a few copy-edits. Description: Added H5Pset/get_small_data_block_size. Copy edits -- several typographic (spelling) corrections. Platforms tested: IE 5 --- doc/html/RM_H5P.html | 116 +++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 107 insertions(+), 9 deletions(-) diff --git a/doc/html/RM_H5P.html b/doc/html/RM_H5P.html index 6be0a9b..8c314a7 100644 --- a/doc/html/RM_H5P.html +++ b/doc/html/RM_H5P.html @@ -170,6 +170,9 @@ many different parameters to be easily manipulated.
  • H5Pget_dxpl_mpio   ||
  • H5Pset_dxpl_multi
  • H5Pget_dxpl_multi +
      +
  • H5Pset_small_data_block_size +
  • H5Pget_small_data_block_size @@ -1620,7 +1623,7 @@ facilitate moving easily between them. used by file drivers that are capable of using data sieving.

    The data sieve buffer is used when performing I/O on datasets - in the file. Using a buffer which is large anough to hold + in the file. Using a buffer which is large enough to hold several pieces of the dataset being read in for hyperslab selections boosts performance by quite a bit.

    @@ -2169,6 +2172,101 @@ facilitate moving easily between them.

    +
    Name: H5Pset_small_data_block_size +
    Signature: +
    herr_t H5Pset_small_data_block_size(hid_t fapl_id, + hsize_t size + ) +
    Purpose: +
    Sets the size of a contiguous block reserved for small data. +
    Description: +
    H5Pset_small_data_block_size reserves blocks of + size bytes for the contiguous storage of the raw data + portion of small datasets. + The HDF5 library then writes the raw data from small datasets + to this reserved space, thus reducing unnecessary discontinuities + within blocks of meta data and improving IO performance. +

    + A small data block is actually allocated the first time a + qualifying small dataset is written to the file. + Space for the raw data portion of this small dataset is suballocated + within the small data block. + The raw data from each subsequent small dataset is also written to + the small data block until it is filled; additional small data blocks + are allocated as required. +

    + The HDF5 library employs an algorithm that determines whether + IO performance is likely to benefit from the use of this mechanism + with each dataset as storage space is allocated in the file. + A larger size will result in this mechanism being + employed with larger datasets. +

    + The small data block size is set as an allocation property in the + file access property list identified by fapl_id. +

    + Setting size to zero (0) disables the + small data block mechanism. +

    Parameters: +
    +
    hid_t fapl_id +
    IN: File access property list identifier . +
    hsize_t size +
    IN: Maximum size, in bytes, of the small data block. +
    + The default size is 2048. +
    +
    Returns: +
    Returns a non-negative value if successful; + otherwise a negative value. + +
    + + +
    +
    +
    Name: H5Pget_small_data_block_size +
    Signature: +
    herr_t H5Pget_small_data_block_size(hid_t fapl_id, + hsize_t *size + ) +
    Purpose: +
    Retrieves the current small data block size setting. +
    Description: +
    H5Pget_small_data_block_size retrieves the + current setting for the size of the small data block. +

    + If the returned value is zero (0), the small data + block mechanism has been disabled for the file. +

    Parameters: +
    +
    hid_t fapl_id +
    IN: File access property list identifier . +
    hsize_t *size +
    OUT: Maximum size, in bytes, of the small data block. +
    +
    Returns: +
    Returns a non-negative value if successful; + otherwise a negative value. + +
    + + +
    +
    Name: H5Pset_preserve
    Signature:
    herr_t H5Pset_preserve(hid_t plist, @@ -2939,7 +3037,7 @@ facilitate moving easily between them.

    The array memb_addr specifies the offsets within the virtual address space, from 0 (zero) to - HADDR_MAX, at wihch each type of data storage begins. + HADDR_MAX, at which each type of data storage begins.

    If relax is set to TRUE (or 1), then opening an existing file for read-only access will not fail @@ -2989,7 +3087,7 @@ facilitate moving easily between them.

    const haddr_t *memb_addr
    IN: The offsets within the virtual address space, from 0 (zero) to HADDR_MAX, - at wihch each type of data storage begins. + at which each type of data storage begins.
    hbool_t relax
    IN: Allows read-only access to incomplete file sets when TRUE. @@ -3176,7 +3274,7 @@ facilitate moving easily between them.
    Purpose:
    Emulates the old split file driver.
    Description: -
    H5Pset_fapl_split is a compatability function that +
    H5Pset_fapl_split is a compatibility function that enables the multi-file driver to emulate the split driver from HDF5 Releases 1.0 and 1.2. The split file driver stored metadata and raw data in separate files @@ -3458,7 +3556,7 @@ fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);
    H5Pset_driver sets the file driver, driver_id, for a file access or data transfer property list, plist_id, and supplies an - optional struct containing the driver-specific properites, + optional struct containing the driver-specific properties, driver_info.

    Need driver_info struct definition. @@ -3472,7 +3570,7 @@ fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);

    hid_t plist_id
    IN: File access or data transfer property list identifier.
    hid_t driver_id -
    IN: Driver indentifier. +
    IN: Driver identifier.
    const void * driver_info
    IN: Optional struct containing driver properties.
    @@ -3501,7 +3599,7 @@ fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);
    Description:
    H5Pget_driver returns the identifier of the low-level file driver associated with the file access property list - or data transfer propert list plist_id. + or data transfer property list plist_id.

    Valid driver identifiers with the standard HDF5 library distribution include the following: @@ -3528,7 +3626,7 @@ fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);

    IN: File access or data transfer property list identifier.
    Returns: -
    Returns a vaild low-level driver identifier if successful. +
    Returns a valid low-level driver identifier if successful. Otherwise returns a negative value.