Subject: Re: CVS commit: src
To: Ross Harvey <>
From: Bill Studenmund <>
List: tech-userlevel
Date: 05/14/1999 16:41:48
On Fri, 14 May 1999, Ross Harvey wrote:

> > From: Bill Studenmund <>
> > To:
> >
> > Module Name:	src
> > Committed By:	wrstuden
> > Date:		Fri May 14 22:36:50 UTC 1999
> >
> > Modified Files:
> > 	src/sbin/newfs: mkfs.c
> > Log Message:
> > Make newfs's spare superblock output nicer. Figure out how wide the
> > largest block number will be, and make the columns wide enough for it. Then
> > make enough columns to fit in an 80 character window.
> Uhh, umm, you could make it even nicer by not printing it at all, or by
> printing just the first (and last?) few block numbers.
> The thing is, FFS wants one superblock per cylinder group. So, actually
> making fewer superblocks for today's large drives would be a bit tricky,
> as it would involve adding the concept of superblock-less cylinder groups.
> But at least we could stop printing them out.

I leave this discussion for tech-userlevel. :-)

As long as they don't look crappy, I don't mind printing them out. The -N
option should always print them out. :-)

Another way to cut down on the number of superblocks is to have more
cylinders per group. I've used 64 one a couple of systems w/ no problem.
On really large fs's, like the 155 GB one I used as an example, that works
out to about 128 MB per group (and 1216 cylinders).

I don't doubt it'd be reasonable to have 128 c/g for some fs's. With
around 40  18 GB disks, you can get into the 700 GB raid size. So say 256
MB/group isn't bad. :-)

Take care,