Subject: Re: strange cpg number in disklabel
To: Raketnet <firstname.lastname@example.org>
From: Frederick Bruckman <email@example.com>
Date: 04/28/2003 09:40:49
On Mon, 28 Apr 2003, Raketnet wrote:
> After editing disklabel and setting the usual 86 cpg for a new partition, I
> get after performing the command newfs another and strange cpg (cylinders per
> group) number, 46376. Can anyone tell me please if this is normal in this "f"
> partition from disklabel. I also tried the parameter -c with newfs trying to
> force what I want but no way I can get it to 86.
> f: 39447954 40970286 4.2BSD 1024 8192 46376 # (Cyl. 40645*- 79779)
Per newfs(8), the default is "the maximum allowed", since about
NetBSD-1.6. In other words, the value given in the label is ignored.
As I recall, this was changed about the time the new dirpref code went
in, to give new file systems the benefit even if they still had the
old label default of 16. "newfs -c" works, except you should have been
warned that 86 isn't a multiple of 16. It may also be too small for a
20gb partition with 8k blocksize. Try saner values, like 2048 for
fragments, 16384 for blocksize, and at least 96 cpg.