newfs and mount vs. half-baked disks

Dan Nelson dnelson at
Tue Nov 4 17:57:12 PST 2003

In the last episode (Nov 04), Wes Peters said:
> I emailed Kirk about this state of affairs and he confirmed that
> newfs was developed with operator intervention in mind.  He suggested
> employing one of the unused flags in the filesystem header as a
> 'consistent' flag, setting it to 'not consistent' at the beginning of
> newfs, and then updating to 'is consistent' at the end.  The
> performance hit in updating all superblock copies at the end is small
> but noticable (< 1s on a rather slow 6GB filesystem).

Would writing a block of zeros to the first (or first n) superblock,
newfs'ing, then rewriting the correct data do the same thing without
affecting the filesystem itself?  I'm thinking about 4.x and cross-OS
portability here.

	Dan Nelson
	dnelson at

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