From mboxrd@z Thu Jan  1 00:00:00 1970
From: Denny Page <dennypage@me.com>
Subject: Re: Extending socket timestamping API for NTP
Date: Mon, 27 Mar 2017 12:18:47 -0700
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Cc: Miroslav Lichvar <mlichvar@redhat.com>, netdev@vger.kernel.org,
        Jiri Benc <jbenc@redhat.com>,
        "Keller, Jacob E" <jacob.e.keller@intel.com>,
        Willem de Bruijn <willemb@google.com>
To: Richard Cochran <richardcochran@gmail.com>
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> On Mar 27, 2017, at 11:28, Richard Cochran <richardcochran@gmail.com> =
wrote:
>=20
> On Mon, Mar 27, 2017 at 09:25:03AM -0700, Denny Page wrote:
>=20
>> I agree that the values in the igb driver are incorrect. They were
>> middle of the range values from the old tables. At least for 100Mb,
>> Intel seems to know that the original table was incorrect. I=E2=80=99ve=
 done
>> extensive measurements of the i210 and i211 at both 100Mb and
>> 1Gb. The =E2=80=9Cexternal link partner=E2=80=9D numbers Intel =
currently publishes
>> for the 100Mb appear accurate.
>=20
> Well, after reading this, I am more convinced than ever that doing the
> correction in user space is the right way.  If the one and only vendor
> who publishes numbers can't even get them straight, how on earth will
> we ever get the drivers right?

I think that on average, the Vendor=E2=80=99s numbers are likely to be =
more accurate than anyone else=E2=80=99s. The concept that independent =
software implementations are going to somehow obtain and maintain better =
numbers is too much of a stretch.

FWIW, My testing indicates that the 100Mb numbers that Intel currently =
publishes are quite accurate. I don=E2=80=99t believe that Intel did the =
driver corrections btw, if memory serves these values were lifted from =
the Mac.

Denny