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boundary="Apple-Mail=_5EBA7805-A5D5-4869-9C92-6CF62C216CB4"; protocol="application/pgp-signature"; micalg=pgp-sha256 MIME-Version: 1.0 X-OriginatorOrg: darbyshire-bryant.me.uk X-MS-Exchange-CrossTenant-Network-Message-Id: 9ccebb9d-e08a-4ef0-0596-08d7debacfd9 X-MS-Exchange-CrossTenant-originalarrivaltime: 12 Apr 2020 08:23:42.6135 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 9151708b-c553-406f-8e56-694f435154a4 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: NhLK9FqSUxI6IIeOUVfnQak8zPE46VwTjypZ9OutBmWu88EpSVMV52YGL6RgT/6jy4jIXL5CDJNAy3PNBuXh6M/u53CcH/Anvo1N4km+i+A= X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR03MB4543 Subject: Re: [Cake] Thinking about ingress shaping & cake X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 12 Apr 2020 08:23:45 -0000 --Apple-Mail=_5EBA7805-A5D5-4869-9C92-6CF62C216CB4 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 > On 10 Apr 2020, at 15:14, Jonathan Morton = wrote: >=20 >=20 > No. If the dequeue rate is never less than the enqueue rate, then the = backlog remains at zero pretty much all the time. There are some = short-term effects which can result in transient queuing of a small = number of packets, but these will all drain out promptly. >=20 > For Cake to actually gain control of the bottleneck queue, it needs to = *become* the bottleneck - which, when downstream of the nominal = bottleneck, can only be achieved by shaping to a slower rate. I would = try 79Mbit for your case. >=20 > - Jonathan Morton >=20 Thanks for correcting my erroneous thinking Jonathan! As I was typing = it I was thinking =E2=80=9Chow does that actually work?=E2=80=9D I = should have thought more. I typically run ingress rate as 97.5% of = modem sync rate (78000 of 80000) which is gives me a little wiggle room = when the modem doesn=E2=80=99t quite make the 80000 target (often = 79500ish). Egress is easy, 99.5% of 20000 ie. 19900, all is wonderful. I=E2=80=99m wondering what the relationship between actual incoming rate = vs shaped rate and latency peaks is? My brain can=E2=80=99t compute = that but I suspect is related to the rtt of the flow/s and hence how = quickly the signalling manages to control the incoming rate. I guess ultimately we=E2=80=99re dependent on the upstream (ISP) shaper = configuration, ie if that=E2=80=99s a large buffer and we=E2=80=99ve an = unresponsive flow incoming then no matter what we do, we=E2=80=99re = stuffed, that flow will fill the buffer & induce latency on other flows. Cheers, Kevin D-B gpg: 012C ACB2 28C6 C53E 9775 9123 B3A2 389B 9DE2 334A --Apple-Mail=_5EBA7805-A5D5-4869-9C92-6CF62C216CB4 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEASyssijGxT6XdZEjs6I4m53iM0oFAl6S0A0ACgkQs6I4m53i M0pSsg//VWZE+jgipJuAbh8pWZHoIQw1V4aTfw2HXJ6kBakFZxvicj/8YO94RZ3l mcY3DI21to9IvSw0KMdioZubTkT7nnZFTmgYABpPdlbRQZlnK0f3UZw6vAz+HeKh +DuZxsi/3VpFys2wTw5GEyhHquzoKWxZhSu6/6FRkINtF5rujes7elkWvRGunO1A 8NTGSY3fw1XxAeES92TCRVW0+4oeARHSTUHSEm7Gg15IaMihkubFjEkgjn1bcZeG Iyy4gGKvXAFIBBqInNOelaw6oS/I6Z94Qdgvdih+FrWYqsa1akTM6iQkbzfaS+Zu QBRi5XW+u8+kx8/iwX5vRWSff1UUFMJCBzwJgQF2papiDegBIVmwgSTlYIKfWiLp nYurG9OffxGgaU7hqXuLR1ZB4QOavPtL72DD05UUvS86EKkuRYrqKMdhI7U6YUm7 SxqhIHLFUk1G0rvCYY67e/0LVU1SxwUQOPiA60NlperwCj5os7ldRMKBhCnMaiGD frvjrJvPxI+mouKZ5z6TwWatnzDSTbiKDRFyb7ORfkM04ZA+qMkRQnKoGqmwdmJm JkgAlpM54H/RXxzGiiM5RHbtJTcOBYCdsjFsA8jyqrqQIFqPFEK+DIOoMs5h5J3k vasN8AQ4s0BxgV+EoKfdPCU7Cz8oLXckLvpzM0zFwTPbbpYj2kM= =9Hr+ -----END PGP SIGNATURE----- --Apple-Mail=_5EBA7805-A5D5-4869-9C92-6CF62C216CB4--