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Date: Sun, 7 Jan 1996 17:49:02 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199601070649.RAA27820@godzilla.zeta.org.au>
To: hackers@FreeBSD.ORG, mrcpu@cdsnet.net
Subject: Re: Number of superblocks on big disks.
Sender: owner-hackers@FreeBSD.ORG
Precedence: bulk

>Is there some real good reason to keep the huge number of superblock 
>backups that exists when formatting very large disks?

It's part of the file system format.  There is a superblock for each
cylinder group.

>a)  It takes forever

Most of the time is for writing the inodes for each cylinder group.

Bruce