9.2.5 Designing HiRDB file system areas for list RDAREAs

This section discusses the design considerations for HiRDB file system areas in which list RDAREAs are to be created.

Organization of this subsection
(1) Design considerations
(2) Design for improved performance

(1) Design considerations

  1. A list is used to store temporary intermediate results of search processing; therefore, it does not need to be as reliable as other RDAREAs. You can create HiRDB file system areas for list RDAREAs in regular files.
  2. If you use the system switchover facility, you can save disk space by allocating HiRDB file system areas for list RDAREAs to character special files because the files can then be shared.

(2) Design for improved performance

  1. If you are creating HiRDB file system areas for list RDAREAs on RAID, you should use character special files to reduce processing time. If you are creating them on any other disk, you should use regular files to reduce processing time.
  2. You should create HiRDB file system areas for list RDAREAs on a hard disk separate from the ones used for the following HiRDB file system areas. In this way, you can distribute input/output operations when searching a list, thereby reducing the processing time.
    • HiRDB file system areas for user RDAREAs
    • HiRDB file system areas for user LOB RDAREAs
    • HiRDB file system areas for work table files