This configuration variable sets the maximum size of a Vision 4 or 5 file segment in bytes. The default value is 2,147,482,112 (i.e., 2GB – 1536), except on older HP/UX machines where it is 1,073,740,288 (i.e., 1GB – 1536) due to an operating system limitation. You may not use larger values, but you can set smaller ones. The default value is the maximum allowed. The value specified will automatically be rounded down to a multiple of the block size of the file being created. For example, if the default V_SEG_SIZE value is used and a file with a block size of 1024 is created, the segment size for that file will be 2,147,481,600 (i.e., 2GB – 2048).
Using a smaller value for the segment size can help if you do not have 2GB free on any disk or for testing purposes. The minimum value allowed is 81,920 bytes. To minimize the number of files created, you should set this value as high as possible.
The segment size of a file is set at file creation time and cannot be modified without recreating the file (i.e., using vutil –rebuild with a different V_SEG_SIZE setting). vutil uses this variable, but since it does not use a configuration file, this variable must be set in the environment.