[dpdk-dev] QoS: The difference of traffic class between subport and pipe in QoS

[lvenyong at 1218.com.cn]

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 at 1218.com.cn
 
From: Dumitrescu, Cristian
Date: 2016-09-07 23:05
To: lvenyong at 1218.com.cn; dev at dpdk.org; users at 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 at 1218.com.cn [mailto:lvenyong at 1218.com.cn] 
Sent: Thursday, September 1, 2016 3:58 AM
To: Dumitrescu, Cristian <cristian.dumitrescu at intel.com>; dev at dpdk.org; users at 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 at 1218.com.cn
 
From: Dumitrescu, Cristian
Date: 2016-09-01 01:44
To: lvenyong; dev at dpdk.org
CC: users at 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 at dpdk.org] On Behalf Of lvenyong
> Sent: Wednesday, August 31, 2016 12:34 PM
> To: dev at dpdk.org
> Cc: users at 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.