<=ToIndex

Physical Design Notes

These notes were an initial design for very compact structure while allowing for very large systems. The fixed limits are not necessary, they were designed to fit into 16 and 32 bit word structures. This is easily changed.

Structure Limits:

1. Area/Conf/Subj - 6/6/4 bits - 64K
2. Subject - 64K msg of 64K length (4GB)
3. Max file space per Area - 512 GB
4. Distribution unit - one or more area(s)

File Structure:

1. RCCS: Partition or equivalent
2. Area: Top level directory
3. Conf: 2nd level directory
4. Subj: 3rd level directory
5. Tree: File
6. Brnch: File segment
7. Msg: 1 or more sequential 128 byte blocks

Index Structure:

Keep super-index in files under conference directory. Keep index for each subject in subject directory. One index header for each Tree. Tree index is built in memory when needed, retained for time (1 hr?), then deleted. It is not stored on disk.