From owner-freebsd-arch  Thu Mar  1  5:44:47 2001
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Date: Thu, 1 Mar 2001 08:44:30 -0500 (EST)
From: Robert Watson <robert@fledge.watson.org>
Reply-To: Robert Watson <robert@fledge.watson.org>
To: Terry Lambert <tlambert@primenet.com>
Cc: "Long, Scott" <scott_long@btc.adaptec.com>,
	"'Garrett Wollman'" <wollman@khavrinen.lcs.mit.edu>, arch@FreeBSD.ORG
Subject: Re: Arch question for a UDF FS driver
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On Thu, 1 Mar 2001, Terry Lambert wrote:

> > > Hash the Unique Id into 31 bits (e.g., u_id % 2147483647).  Renumber
> > > any collisions into the space above 2**31.  You would still need to
> > > keep some state when there is a collision, but if the Ids are
> > > assigned sequentially then you are likely to win most of the time.
> > 
> > Interesting idea.  Like I said, consuming 32 bits within the life of the
> > filesystem is going to be pretty hard.
> > 
> > > I don't see what this has to do with vget(), however.
> > 
> > not vget() itself, the vget vfsop.  Unless I'm totally clueless here, the
> > vget vfsop is supposed to return the vnode that repesents the passed in
> > ino_t.
> 
> The question to ask yourself is "under what circumstances do I care
> about the ino_t?".
> 
> My personal take would be to appeal to the Apple people here,
> since they have already implemented one of these things, and
> know how they did it, and the technical reasons why.
> 
> My gut reaction would be to give ownership of the vnodes to the
> FS itself, and ignore the problem (search for the string "TFS"
> in the FS releated kernel code to see what I mean).
> 
> 
> 					Terry Lambert
> 					terry@lambert.org
> ---
> Any opinions in this posting are my own and not those of my present
> or previous employers.
> 
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