Hi, regarding the question: how timestamps come from ingress to egress pipe?
Well this depends (on the P4 abstraction) on the P4 version you use. As far as I remember (it is a long time ago) in P4_14 metadata (which can store the timestamp) are handed over implicitly from ingress to egress. In P4_16 you have do do this explicitly in the Deparser of Ingress and Parser of Egress: Simply said you just write the timestamp before the Ethernet header. You can see this here in line 64 to 80: https://github.com/ralfkundel/p4-codel/blob/master/targets/tofino/srcP4/l1switchCodel.p4 best, Ralf Am 21.04.21 um 04:42 schrieb Dave Taht: > https://www.comsys.rwth-aachen.de/fileadmin/papers/2021/2021-kunze-aqm-tofino-p4.pdf > > For a codel comparison, see: > > https://arxiv.org/pdf/2010.04528v1.pdf > > Where the authors show that fq_codel is feasible on the PISA platform... > > but a direct comparison between the two papers is not possible. What I > don't understand about the above paper is how codel timestamps are > passed from ingress to egress. > -- ________________________________________________ Ralf Kundel, M.Sc. Technical University of Darmstadt Dept. of Electrical Engineering and Information Technology Multimedia Communications Lab (KOM) Adaptive Communication Systems Group (ACS) Postal address: TU Darmstadt, FB 18, KOM, Rundeturmstr. 10, 64283 Darmstadt, Germany Location: S3|20 - 216 Tel: +49 6151 16-20855 Email: [email protected] Web: http://www.kom.tu-darmstadt.de ___________________________________________________________ _______________________________________________ Bloat mailing list [email protected] https://lists.bufferbloat.net/listinfo/bloat
