-*- text -*-
Hi 
(this is the only documentation, for now)

NAME:     updateNFScache

TARGET:   networks

THE IDEA: is to have frequently-used (and not so often changing)  files on a local disk instead of on a (mounted) remote one. 

USAGE:	  updateNFScache [-q]	 
------	  -q supresses logging to the stdout,  still files  .deleted, .updated, .added are written in each - say -  `shadow' directory.


STATUS:   still in heavy progress. see PLANS bellow.

EXAMPLE:  I NFS-mount /usr on some five computers but I want to store the frequently used libraries (and even programs etc. emacs,
          gawk...) on every computer. Simply put I invest disk-space to obtain more speed and I want to invest good.


DETAILED DESCRIPTION:
          Q: what are the most-frequently used things (how to discover them) ??
          A: 1) As for programs, you can ask *hash*  Bash-builtin. Have your logout script save it and analyze it now and then. This will be in the
	            next release, sorry. 
             2) In general (man-pages, libraries etc) you can approximate with the most-recently used files. Now that's simple --
          look at access times. And that's what I do.


          Q: how to keep up-to-date?
          A: have the cron do it for you. Just run the script *updateNFScache* frequently.


          Q: What does it do?
          A: Well, to say briefly:
             a) deletes long-time-unused files.
             b) updates (with new versions) files which remain in cache.
             c) adds recently used files.

           
          Q: what can/should  be modified?
          A: * times to consider old, new may be changed:
             after OLDT  day  not being used the file is removed.
             file used (by another work-station) used in NEWT  days  enters.
             ... these could be computed  (imagine you do not  work on weekends) .. we should relate it to the last times  we used
             updateNFScache. TO BE DONE !!
             
             * installing new software should delete the files !!! to be done yet.

             
CHANGES:  version 1.1: hard-links are copied as such.

          
(KNOWN-)PROBLEMS: file used by 1 user enters the cache of all users for the first time and then exits after OLDT days.



PLANS:  as pointed-out above: analyze the results of *hash*; make *install*  updateNFScache-aware, calculate the time-boundaries better !!
	It seems to me, I will have to migrate from simple shell (Bash) to perl or something similar.


AUTHOR: Michal Maruka 
EMAIL:  mmaruska@tin.it



Placed in public domain by Michal Maruka, 1997.  Share and enjoy!
