Queations about buffindexed

[Daniel G. Thompson]

Documentation is not clear so I must ask here for some clarification.
I am replacing two news servers that are currently using tradindexed
overview and CNFS. I would like to change the overview to use
buffindexed but have a few questions, so here goes.

1: Do the buffindexed buffers get cleared by Expire or do they continue to
    grow until they run out of buffer space, then throttle the server?
Documentation
    indicates the fact that the overview info does not simply return to the
top of
    buffers and start writing over old data the way the CNFS does.

2: Considering that buffindexed has some sort of a way to clean itself of
useless
    old data are there any general rules as to the total size of the buffers
in relation
    to the size of the spool? My spool size on each of the new servers is
700Gb
    using CNFS. The question then is how much room should I allocate for the
    overview buffers if I am to run these servers using buffindexed ?

If there is other documentation or a how to that will answer these questions
a
simple pointer in the right direction would be appreciated.

Thank You,
Dan Thompson
dan at waycom.com