From: "J. Bruce Fields" <bfields@fieldses.org>
Subject: Re: HEADS-UP: nearing nfs-utils 1.1.0 and statd changes.
Date: Mon, 19 Mar 2007 21:14:58 -0400
Message-ID: <20070320011458.GA31225@fieldses.org>
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Cc: nfs@lists.sourceforge.net
To: "Talpey, Thomas" <Thomas.Talpey@netapp.com>
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On Mon, Mar 19, 2007 at 08:30:42PM -0400, Talpey, Thomas wrote:
> At 07:02 PM 3/19/2007, J. Bruce Fields wrote:
> >so.  That means that we no longer need to forget those clients that
> >haven't reclaimed at the end of grace--we *can* if we want to, but it's
> >not urgent because (as long as we also rememember "boot" times), we can
> >notice at the next boot that their last reclaim was too long ago.
> 
> In fact, it's highly desirable to keep their state around, until some
> conflict arises. Maybe the network is partitioed, etc. It's the Internet
> Principle, in addition to being appropriately lazy. 

You're getting a little ahead of me here.  I'm not talking about trying
to allow reclaims after the grace period ends--I agree that that would
be nice, but I don't see a really simple way to do that.  I'm just
talking about how we implement the simplest reboot recovery behavior.

Currently we're *not* doing what the rfc suggests--keeping a record
with timestamp of first open, etc.--instead we're basically remembering
just the one bit per client (is this client known to us or not), which
means we *must* synchronously invalidate every client as we exit the
grace period.  That's awkward.

> But I have a question - what's "too long ago"? Do you propose
> refusing a reclaim after some interval?

So by "too long ago" I mean "more than one boot ago".

--b.

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