Re: QoS: The difference of traffic class between subport and pipe in QoS

Hi Cristian,

Thanks for your explanation. I haved learned. 
The  traffic class in function of rte_sched_port_pkt_write is both subport's and pipe's .

Regards,
enyong



lvenyong@1218.com.cn
 
From: Dumitrescu, Cristian
Date: 2016-09-07 23:05
To: lvenyong@1218.com.cn; dev@dpdk.org; users@dpdk.org
Subject: RE: RE: [dpdk-dev] QoS: The difference of traffic class between subport and pipe in QoS
Traffic class is really the type of traffic, e.g. voice, real-time video (like RTP), best effort (TCP-based video, file downloads, etc). Each traffic type has different requirements in terms on latency/delay, jitter/delay variation, loss rate, bandwidth, etc.
 
The levels of our scheduling hierarchy are: (1) port (output network interface), (2) subport (port slide, i.e. group of pipes/users), (3) pipe (user/subscriber), (4) traffic class (type of traffic), (5) packet queue. The rationale for having a TC limit at subport and pipe levels is to rate limit the about of that traffic type that the user (pipe level TC rate) or the group of users (subport level TC rate) are allowed to send. For example, you might want to restrict the amount of real-time video each user is sending to 1 Mbps, but also the amount to real-time video the group of e.g. 1000 users to 500Mbps; then packets might be restricted from being scheduled by either the user-level limit or the group-level limit, whichever is hit first.
 
Here is a Youtube video on DPDK QoS in case you’re tired of reading the docs or the code: https://youtu.be/_PPklkWGugs
 
Regards,
Cristian
 
From: lvenyong@1218.com.cn [mailto:lvenyong@1218.com.cn] 
Sent: Thursday, September 1, 2016 3:58 AM
To: Dumitrescu, Cristian <redacted>; dev@dpdk.org; users@dpdk.org
Subject: Re: RE: [dpdk-dev] QoS: The difference of traffic class between subport and pipe in QoS
 
Thanks for your answer!  But i haved not understand it. 
what is the role of traffic class in subport, and the  relationship with the traffic class in pipe ?
The  traffic class in function of rte_sched_port_pkt_write is subport's or pipe's ?
void rte_sched_port_pkt_write(struct rte_mbuf *pkt,
                                   uint32_t subport, uint32_t pipe, uint32_t traffic_class,
                                   uint32_t queue, enum rte_meter_color color);
 


lvenyong@1218.com.cn
 
From: Dumitrescu, Cristian
Date: 2016-09-01 01:44
To: lvenyong; dev@dpdk.org
CC: users@dpdk.org
Subject: RE: [dpdk-dev] QoS: The difference of traffic class between subport and pipe in QoS
 
 

-----Original Message-----
From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of lvenyong
Sent: Wednesday, August 31, 2016 12:34 PM
To: dev@dpdk.org
Cc: users@dpdk.org
Subject: [dpdk-dev] QoS: The difference of traffic class between subport and
pipe in QoS

HI !

Is there difference of traffic class between subport and pipe in QOS ?

After read prog_guide-2.2.pdf we kown that the scheduling hierarchy is port,
subport, pipe, traffic class and queue. But the traffic class both in
subport and pipe appeared in example of qos_sched .

[subport 0]
tb rate = 1250000000           ; Bytes per second
tb size = 1000000              ; Bytes
tc 0 rate = 1250000000         ; Bytes per second
tc 1 rate = 1250000000         ; Bytes per second
tc 2 rate = 1250000000         ; Bytes per second
tc 3 rate = 1250000000         ; Bytes per second
tc period = 10                 ; Milliseconds
pipe 0-4095 = 0                ; These pipes are configured with pipe
profile 0
; Pipe configuration
[pipe profile 0]
tb rate = 305175               ; Bytes per second
tb size = 1000000              ; Bytes
tc 0 rate = 305175             ; Bytes per second
tc 1 rate = 305175             ; Bytes per second
tc 2 rate = 305175             ; Bytes per second
tc 3 rate = 305175             ; Bytes per second
tc period = 40                 ; Milliseconds

Thanks

 
There are 4x traffic classes. You can enforce a limit on the amount of traffic belonging to each traffic class at the subport level, as well as at the level of each pipe if you want.