Subject: Re: likely dumb question
To: der Mouse <mouse@Collatz.McRCIM.McGill.EDU>
From: Ken Wellsch <kcwellsc@math.uwaterloo.ca>
List: port-sun3
Date: 04/24/1996 23:10:29
| I suspect the space change "magic" was due not to the new filesystem
| layout but rather to the dump/restore.  Most likely, it seems to me, is
| that you have files with big potential holes that are filled in on your
| current fs, and dump was smart enough to turn the potential holes into
| actual holes.  (Of course, whether such behavior really is "smart" is
| debatable.  My personal preference would be for dump/restore to create
| holes where, and only where, the original had holes, absent explicit
| instructions to the contrary.  That's the way my tar works....)

Well, actually, the available total space listed by "df" for the partition
had increased dramatically, for example 1Mb on the ~30Mb root partition
I had and something like nearly 20Mb on /usr (~250Mb partition). After
the dump/restore the consumed block count nearly matched.  I often look
at this second number to tell if things "probably" transferred okay.

But given the fact that after I did a "dd" of the old disk, then did a
"newfs," then a dump/restore only to have boot fail (after the PROM loaded
the boot but on the first stage boot I'm guessing - I just got "exception"
after my "b" command) this added space may has a serious cost 8-).
A straight "dd" boots as expected though.

Thanks for the pointer on your label program - I'll try and track
down a copy!

-- Ken