IBM High Performance Storage System HPSS Installation Manual page 76

Definitions for the DB2 tables are as follows:
Bitfile Disk Allocation Maps. (BFDISKALLOCREC) For each bitfile stored on disk, one or more
rows will be created in the Disk Allocation Maps table. The number of rows is determined by the
storage segment size in the Storage Class in which the files are stored and the average file size stored
in that Storage Class.
Bitfile Disk Segments. (BFDISKSEG) For a bitfile stored on disk, one or more s will be
row
created in the bitfile disk segment table. Because bitfile disk segments track the contiguous
pieces of a bitfile, there normally will be only one disk segment per file.
row
Bitfile Tape Segments. (BFTAPESEG) For a bitfile stored on tape, one or more rows will be created
in the bitfile tape segment table. Under normal conditions, one bitfile tape segment row is expected
for each tape on which the file is stored. It is safe to assume for each bitfile stored on tape, two bitfile
segment records are needed.
Bitfiles. (BITFILE) One row is created in the bitfile metadata table for each bitfile. The amount of
space allocated for this DB2 table will normally limit how many bitfiles can be created. Regardless of
how many copies of a bitfile exist and whether the bitfile is spread across disk and/or tape, only one
bitfile row is created for the file.
Name Space Objects. (NSOBJECT) Each name space object (file, fileset, directory, hard link,
junction or soft link) uses one row in the NSOBJECT table.
Name Space Text. (NSTEXT) A name space text row exists for each name space object that has a
comment or is a symbolic link. These text rows are variable length with a maximum size of 1023
HPSS Installation Guide July 2008
Release 6.2 (Revision 2.0) 76