Re: [PATCH 86/87] fs: switch timespec64 fields in inode to discrete integers

Steve French <[email protected]> Sat, 30 Sep 2023 09:50:41 -0500
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Message-ID <CAH2r5ms14hPaz=Ex2a=Dj0Hz3XxYLRKFj_rHHekznTbNJ_wABQ@mail.gmail.com> 
On Fri, Sep 29, 2023 at 3:06 AM David Howells via samba-technical
<[email protected]> wrote:
>
>
> Jeff Layton <[email protected]> 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 make
> sense to switch internally to Microsoft-style 64-bit timestamps with their
> 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 and
various Windows filesystems)


-- 
Thanks,

Steve