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From: Robert Watson <rwatson@FreeBSD.org>
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To: Jeff Roberson <jroberson@jroberson.net>
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Cc: arch@freebsd.org
Subject: Re: VOP_LEASE
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On Sat, 12 Apr 2008, Jeff Roberson wrote:

> As far as I can tell this has never been used.  Unless someone can show me 
> otherwise I'm going to go ahead and remove it.

(A year, +/- one week, passes...)

Since we now have an NFSv4 client/server and it doesn't use VOP_LEASE, and 
NQNFS is long-gone, I propose we revisit removing VOP_LEASE, which you 
proposed last year but presumably died as a result of a discussion of whether 
it might be useful again someday.  While not a huge overhead, in practice it 
means a passage through the VOP vector for every I/O operation, and it 
certainly adds lines of code.  Assuming no objections in the few days, I'll 
toast VOP_LEASE implementation and calls from the rest of the stack from 8.x 
so that it's gone before we ship 8.0.

Robert N M Watson
Computer Laboratory
University of Cambridge