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Date: Fri, 21 Sep 2007 09:19:19 -0400
From: Gary Palmer <gpalmer@freebsd.org>
To: Ivan Voras <ivoras@freebsd.org>
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Cc: freebsd-fs@freebsd.org
Subject: Re: Writing contigiously to UFS2?
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On Fri, Sep 21, 2007 at 02:50:14PM +0200, Ivan Voras wrote:
> Eric Anderson wrote:
> 
> >The largest file size per chunk in a cylinder group is calculated at 
> >newfs time, which determines also how many cylinder groups there should 
> >be.  I think the largest size I've seen was something in the 460MB-ish 
> >range, meaning any contiguous write above that would span more than one 
> >cylinder group.
> 
> Hmm, how did you manage to create a file system with such large cylinder 
> groups? I've experimented with smallnum-TB file systems and still 
> couldn't make them larger than around 190 MB (though I wasn't actively 
> trying, just observed how they turned out).

Presumably by using the -c parameter to newfs.

The original poster might get some traction out of a combination of
-c and -e parameters to newfs, although the fundamental behaviour
will remain unchanged.