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From:   Steve French <smfrench@gmail.com>
Date:   Sat, 30 Sep 2023 09:50:41 -0500
Message-ID: <CAH2r5ms14hPaz=Ex2a=Dj0Hz3XxYLRKFj_rHHekznTbNJ_wABQ@mail.gmail.com>
Subject: Re: [PATCH 86/87] fs: switch timespec64 fields in inode to discrete integers
To:     David Howells <dhowells@redhat.com>
Cc:     Jeff Layton <jlayton@kernel.org>,
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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