🚀 go-pugleaf

romig@brachiosaur.cis.ohio-state.edu (Steve Romig) writes:
>I'm curious - how much space does the online index take up?  I'd
>imagine that it would be proportional to the number of files backed
>up, which might be hard to estimate...

	18 months of NSR index for 9 machines took 80 megs with just
incrementals and no index cleaning. I purged tapes #1 and #2 a few
months ago and it gave me back 20 megs. (I guess #1 and #2 had a
lot of directory entries on them). I'm not sure how the index size
relates to the number of times a file is backed up. I *assume* that
a dated tuple:
{ inode, tape, date }
	gets stored each time a file's directory entry is re-saved.
Possibly my approach of doing incremental-only is a big win here.
I'm interested to know what other people see...?

>I'd swear that I've heard people throw around figures like "10% of the
>amount that's backed up", which seems absurd.  In our case, since we
>have about 160 Gb on tape at the moment, we're talking about an online
>index of 16 Gb using that ratio...yow!

	I'm handling a measly 10gig or so. Of course, since I only
do incrementals, I only wind up saving about 10Mb to tape per night,
so figure the indexes grow very very slowly. Possibly more so because
most of the stuff that changes is syslog files, mail queue and whatnot.

	I DO NOT BACK UP NEWS.

	This helps, I suspect.

mjr.