From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steve French <smfrench@gmail.com>
Subject: Re: [PATCH 86/87] fs: switch timespec64 fields in inode to discrete integers
Date: Sat, 30 Sep 2023 09:50:41 -0500
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To: David Howells <dhowells@redhat.com>
Cc: Jeff Layton <jlayton@kernel.org>, Latchesar Ionkov <lucho@ionkov.net>, Konstantin Komarov <almaz.alexandrovich@paragon-software.com>, "Rafael J . Wysocki" <rafael@kernel.org>, "Darrick J. Wong" <djwong@kernel.org>, Anders Larsen <al@alarsen.net>, Carlos Llamas <cmllamas@google.com>, Andrii Nakryiko <andrii@kernel.org>, Mattia Dongili <malattia@linux.it>, Hugh Dickins <hughd@google.com>, John Johansen <john.johansen@canonical.com>, Yonghong Song <yonghong.song@linux.dev>, Alexander Gordeev <agordeev@linux.ibm.com>, Christoph Hellwig <hch@lst.de>, Mike Marshall <hubcap@omnibond.com>, Paulo Alcantara <pc@manguebit.com>, linux-xfs@vger.kernel.org, Michael Ellerman <mpe@ellerman.id.au>, James Morris <jmorris@namei.org>, Christophe Leroy <christoph>

On Fri, Sep 29, 2023 at 3:06=E2=80=AFAM David Howells via samba-technical
<samba-technical@lists.samba.org> wrote:
>
>
> Jeff Layton <jlayton@kernel.org> wrote:
>
> > Correct. We'd lose some fidelity in currently stored timestamps, but as
> > Linus and Ted pointed out, anything below ~100ns granularity is
> > effectively just noise, as that's the floor overhead for calling into
> > the kernel. It's hard to argue that any application needs that sort of
> > timestamp resolution, at least with contemporary hardware.
>
> Albeit with the danger of making Steve French very happy;-), would it mak=
e
> sense to switch internally to Microsoft-style 64-bit timestamps with thei=
r
> 100ns granularity?

100ns granularity does seem to make sense and IIRC was used by various
DCE standards in the 90s and 2000s (not just used for SMB2/SMB3 protocol an=
d
various Windows filesystems)


--=20
Thanks,

Steve