From owner-freebsd-current Wed Feb 22 01:03:45 1995 Return-Path: current-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.9/8.6.6) id BAA01564 for current-outgoing; Wed, 22 Feb 1995 01:03:45 -0800 Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.2.228.34]) by freefall.cdrom.com (8.6.9/8.6.6) with ESMTP id BAA01556 for ; Wed, 22 Feb 1995 01:03:29 -0800 Received: (from bde@localhost) by godzilla.zeta.org.au (8.6.9/8.6.9) id TAA02348; Wed, 22 Feb 1995 19:57:50 +1100 Date: Wed, 22 Feb 1995 19:57:50 +1100 From: Bruce Evans Message-Id: <199502220857.TAA02348@godzilla.zeta.org.au> To: regent.e-technik.tu-muenchen.de!jhs@sbstark.cs.sunysb.edu, starkhome!gene@sbstark.cs.sunysb.edu Subject: Re: newfs: sectors per cylinder (4096) disagrees with disk label (36) Cc: current@FreeBSD.org Sender: current-owner@FreeBSD.org Precedence: bulk >Newfs now ignores the disklabel and uses defaults of 1 track/cyl and 4096 >sectors/track. You can override by giving explicit arguments. >However, the way the changes have been made strikes me as somewhat kludgy. >Would it be possible for newfs to do the following: > (1) Check /etc/disktab for info on the partition. Use these > parameters if available. > (Put the 4096/1 stuff in here.) > (2) If /etc/disktab has no info, look at the disklabel. > Pay attention to these parameters if available. It already looks at /etc/disktab (if a disktab entry is specified) and at the label. I wouldn't want it replacing values in the label with values in the disktab entry for the disk type givel in the label when a disktab entry is not specified. The point is that the values given in disktab entries and labels are often BAD. They are supposed to be blown away. Poul actually only intended the values in disklabels to be ignored, but the same problem occurs for disktab entries. However, there are some disktab and label entries that give the physical geometry (floppies and old drives). Newfs should use these geometries unless the old ufs support for fixed geometries doesn't actually work (I don't think it can unless all the seek times are known). I think the correct solution is to put the geometry that you want newfs to use in the label. The geometry in the label isn't used for many things other than newfs. It is used for booting and by fdisk. Disk slicing will provide separate labels for the whole disk and the BSD slice (even when the BSD slice is the whole disk) so it will be possible to have separate geometries for booting/fdisk and newfs. Bruce