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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Bruce Fields <bfields@fieldses.org>
CC:     Dai Ngo <dai.ngo@oracle.com>, Jeff Layton <jlayton@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
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Subject: Re: [PATCH RFC v12 3/3] nfsd: Initial implementation of NFSv4
 Courteous Server
Thread-Topic: [PATCH RFC v12 3/3] nfsd: Initial implementation of NFSv4
 Courteous Server
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Date:   Thu, 10 Feb 2022 16:52:15 +0000
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> On Feb 10, 2022, at 11:32 AM, J. Bruce Fields <bfields@fieldses.org> wrot=
e:
>=20
> I was standing in the shower thinking....
>=20
> We're now removing the persistent client record early, after the first
> lease period expires, instead of waiting till the first lock conflict.
>=20
> That simplifies conflict handling.
>=20
> It also means that all clients lose their locks any time a crash or
> reboot is preceded by a network partition of longer than a lease period.
>=20
> Which is what happens currently, so it's no regression.
>=20
> Still, I think it will be a common case that it would be nice to handle:
> there's a network problem, and as a later consequence of the problem or
> perhaps a part of addressing it, the server gets rebooted.  There's no
> real reason to prevent clients recovering in that case.
>=20
> Seems likely enough that it would be worth a little extra complexity in
> the code that handles conflicts.
>=20
> So I'm no longer convinced that it's a good tradeoff to remove the
> persistent client record early.

Would it be OK if we make this change after the current work is merged?


--
Chuck Lever