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Subject: Re: DSACK
From: Michael Tuexen <tuexen@freebsd.org>
In-Reply-To: <SN4PR0601MB3728752D55B7231BC4CF22B586780@SN4PR0601MB3728.namprd06.prod.outlook.com>
Date: Sat, 23 Feb 2019 11:25:26 +0100
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To: "Scheffenegger, Richard" <Richard.Scheffenegger@netapp.com>
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> On 23. Feb 2019, at 10:29, Scheffenegger, Richard =
<Richard.Scheffenegger@netapp.com> wrote:
>=20
> Hi,
>=20
> A colleague pointed me to the stack (HEAD) no longer emitting DSACK =
options a few days ago...
>=20
> I was under the impression, that older versions of FreeBSD would send =
out DSACKs for spurious duplicate packets.
>=20
> But when I try this script against HEAD, regular cumulative ACKs =
without DSACK blocks are showing up.
>=20
> Currently bandwidth starved - but was that a conscious decision? Or =
was me observing DSACKs never a thing?
I would say if it is working in stable/11, but not in stable/12 and =
head, it is a regression.

Best regards
Michael
>=20
> Thanks a lot,
>   Richard
>=20