Subject: Re: major hier(7) overhauls?
To: NetBSD Userlevel Technical Discussion List <tech-userlevel@netbsd.org>
From: Greg A. Woods <woods@most.weird.com>
List: tech-userlevel
Date: 12/23/1998 13:41:26
[ On Wed, December 23, 1998 at 19:50:28 (+1100), Giles Lean wrote: ]
> Subject: Re: major hier(7) overhauls? 
>
> On Sun, 20 Dec 1998 01:23:57 -0500 (EST)  Greg A. Woods wrote:
> >
> > As some of you know my favourite "major overhaul" would be to eliminate
> > /usr and move the system entirely back into one self-consistent,
> > single-level, hierarchy.  We no longer need to split the system over
> > separate disk packs, not because of size, not because of speed, not even
> > because of reliability and robustness.
> 
> i386 BIOS boot limitations?

I guess it depends on exactly what disks and BIOS you have, but I've no
problem getting a 500MB partition on a 4GB SCSI disk to boot
(1024*255*63=16450560 sectors).  Even on a 1GB disk it should still work
(1024*63*32=2064384 sectors), and so far as I know there are no major
issues with disks <1GB.  Maybe I'm fooling myself and have just been
lucky because /boot is still very early on the disk -- I don't know.
Either way I can hardly wait for those OpenBIOS folks to get going!  ;-)
(and I do hope they use the OpenFirmware specs, but it doesn't look like
they're going to....)

That 500MB is extreme over-kill too.  A combined / and /usr, including
X11, is only ~160MB, and without X11 is only about half that, at least
on an i386.  I am putting /usr/local and /usr/pkg on a separate
filesystem (and separate spindle! ;-) though (and combining them because
I've no idea how the split will work out in the long term).

My -current system looks like this now (3 4.5GB disks) (X11 is only on /
so far, not /altroot):

12:59 [49] $ df -k
Filesystem           1K-blocks     Used    Avail Capacity  Mounted on
/dev/sd0a               490591   154284   311777    33%    /
/dev/sd0e               490591     1560   464501     0%    /var
/dev/sd1e               490591        1   466060     0%    /tmp
/dev/sd1a               490591    81121   384940    17%    /altroot
/dev/sd0f              2834732   979599  1713396    36%    /cvs
/dev/sd1f              2834732    45760  2647235     1%    /opt
/dev/sd2h              3815222   280437  3344023     7%    /work

Yes, I'm showing off my new toy!

I am wasting a lot of space, but I don't want to have to re-partition
this thing any time soon.  I've also put 500MB swap on each disk, so if
I need a wee bit more somewhere I can still juggle things around!  ;-)

/altroot is my "quick" recovery scheme (in case -current screws
something up), and where I'll set DESTDIR for testing new builds before
I take them 100% live.  Note that having / and /usr on the same
filesytem makes recover even quicker and keeping things in sync even
simpler.  The other partitions will be backed up periodically, usually
with incremental dumps, and /home is NFS mounted from my main server.

Now I've got to go get ready to re-build my 1.3.x/i386 machine with
1.3.3 and build a whole lot of packages on it for a client, and then
install 1.3.3 on a sparc for testing in preparation for doing a re-build
and upgrading my main sparc server.  Somewhere in there I want to get
1.3.3 and -current on my Multia's, once I've fixed them, and get one
ready to take over firewall/router duty....  I guess it won't all happen
this year!

-- 
							Greg A. Woods

+1 416 218-0098      VE3TCP      <gwoods@acm.org>      <robohack!woods>
Planix, Inc. <woods@planix.com>; Secrets of the Weird <woods@weird.com>