0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ======================
0004 DCTCP (DataCenter TCP)
0005 ======================
0006
0007 DCTCP is an enhancement to the TCP congestion control algorithm for data
0008 center networks and leverages Explicit Congestion Notification (ECN) in
0009 the data center network to provide multi-bit feedback to the end hosts.
0010
0011 To enable it on end hosts::
0012
0013 sysctl -w net.ipv4.tcp_congestion_control=dctcp
0014 sysctl -w net.ipv4.tcp_ecn_fallback=0 (optional)
0015
0016 All switches in the data center network running DCTCP must support ECN
0017 marking and be configured for marking when reaching defined switch buffer
0018 thresholds. The default ECN marking threshold heuristic for DCTCP on
0019 switches is 20 packets (30KB) at 1Gbps, and 65 packets (~100KB) at 10Gbps,
0020 but might need further careful tweaking.
0021
0022 For more details, see below documents:
0023
0024 Paper:
0025
0026 The algorithm is further described in detail in the following two
0027 SIGCOMM/SIGMETRICS papers:
0028
0029 i) Mohammad Alizadeh, Albert Greenberg, David A. Maltz, Jitendra Padhye,
0030 Parveen Patel, Balaji Prabhakar, Sudipta Sengupta, and Murari Sridharan:
0031
0032 "Data Center TCP (DCTCP)", Data Center Networks session"
0033
0034 Proc. ACM SIGCOMM, New Delhi, 2010.
0035
0036 http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf
0037 http://www.sigcomm.org/ccr/papers/2010/October/1851275.1851192
0038
0039 ii) Mohammad Alizadeh, Adel Javanmard, and Balaji Prabhakar:
0040
0041 "Analysis of DCTCP: Stability, Convergence, and Fairness"
0042 Proc. ACM SIGMETRICS, San Jose, 2011.
0043
0044 http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf
0045
0046 IETF informational draft:
0047
0048 http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00
0049
0050 DCTCP site:
0051
0052 http://simula.stanford.edu/~alizade/Site/DCTCP.html
