ECN counters

[rszarecki]

Change Scope

Adds per queue packets, octets counters for traffic that:

• has ECN field remarked form ECT(0), ECT(2) to CE dodepoint.
• has beed enqueued while selected by AQN (such WRED)

module: openconfig-qos
  +--rw qos
     +--rw interfaces
        +--rw interface* [interface-id]
           +--rw output
              +--rw queues
                 +--rw queue* [name]
                    +--ro state
                       +--ro name?                       string
                       +--ro queue-management-profile?   -> ../../../../../../../queue-management-profiles/queue-management-profile/config/name
                       +--ro max-queue-len?              oc-yang:counter64
                       +--ro avg-queue-len?              oc-yang:counter64
                       +--ro transmit-pkts?              oc-yang:counter64
                       +--ro transmit-octets?            oc-yang:counter64
                       +--ro dropped-pkts?               oc-yang:counter64
                       +--ro dropped-octets?             oc-yang:counter64
                       +--ro ecn-marked-pkts?            oc-yang:counter64
                       +--ro ecn-marked-octets?          oc-yang:counter64
                       +--ro ecn-selected-pkts?          oc-yang:counter64
                       +--ro ecn-selected-octets?        oc-yang:counter64

Table below shows counter's behaviour:

ingressing packets ECN bits	queue utilization	ecn-selected-pkts, ecn-selected-octets	ecn-marked-pkts , ecn-marked-octets
non-ECN (00)	below RED min-treshold	not increments	not increments
non-ECN (00)	between RED min-treshold and max-threshold	increments w/ probability rate derived form RED slope	not increments
non-ECN (00)	above RED max-treshold	increments	not increments
ECT (01)	below RED min-treshold	not increments	not increments
ECT (01)	between RED min-treshold and max-threshold	increments w/ probability rate derived form RED slope	increments w/ probability rate derived form RED slope
ECT (01)	above RED max-treshold	increments	increments
ECT (10)	below RED min-treshold	not increments	not increments
ECT (10)	between RED min-treshold and max-threshold	increments w/ probability rate derived form RED slope	increments w/ probability rate derived form RED slope
ECT (10)	above RED max-treshold	increments	increments
CE (11)	below RED min-treshold	not increments	not increments
CE (11)	between RED min-treshold and max-threshold	increments w/ probability rate derived form RED slope	not increments
CE (11)	above RED max-treshold	increments	not increments

Change is backward compatible

Platform Implementations

Arista: link to documentation

show qos interface et25/3 ecn counters queue
Ethernet25/3:
  Tx-Queue             Marked Packets
-----------    -----------------------
0                                   -
2                                   -
3                                   0
4                                   0
5                            10000000
6                                   0
7                                   0

Arista implements ecn-selected-pkts, ecn-selected-octets

IExtreme Networks: link to documentation

device# show qos red statistics interface eth 0/1

Statistics for interface: Eth 0/1
       Port Statistics:
           Packets Dropped: 147, Queue Full Drops: 222, ECN Marked: 234

Dell/EMC link to documentation

DellEMC#show qos statistics wred-ecn

--------------------ECN Packet Counter Details------------------------
Interface MarkedTxPkts TotalDropPkts(ECN Enabled Queues)
----------------------------------------------------------------------
Fo 1/32/1 122226925 122178941
Fo 1/1/1 340808237 169105794
Fo 1/17/1 0 0

Cisco IOS XR example:

Router# show policy-map int hu 0/0/0/35 output 
TenGigE0/0/0/6 output: pm-out-queue

HundredGigE0/0/0/35 output: egress_qosgrp_ecn
 
Class tc7
  Classification statistics          (packets/bytes)     (rate - kbps)
    Matched             :           195987503/200691203072         0
    Transmitted         :           188830570/193362503680         0
    Total Dropped       :             7156933/7328699392           0
  Queueing statistics
    Queue ID                             : 18183
    Taildropped(packets/bytes)           : 7156933/7328699392
 
    WRED profile for
    RED Transmitted (packets/bytes)            : N/A
    RED random drops(packets/bytes)            : N/A
    RED maxthreshold drops(packets/bytes)      : N/A
    RED ecn marked & transmitted(packets/bytes): 188696802/193225525248

Cisco implements ecn-marked-pkts, ecn-marked-octets

[OpenConfigBot]

Major YANG version changes in commit 1a751ce:

[OpenConfigBot]

Compatibility Report for commit 1a751ce:
✅ pyangbind@6b85c2b

[dplore]

Reviewed on OC Operators call September 19, 2023 without objection. Thanks for the contribution

[dplore]

/gcbrun