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diff --git a/src/vnet/devices/dpdk/qos_doc.md b/src/vnet/devices/dpdk/qos_doc.md deleted file mode 100644 index 7c064246e60..00000000000 --- a/src/vnet/devices/dpdk/qos_doc.md +++ /dev/null @@ -1,411 +0,0 @@ -# QoS Hierarchical Scheduler {#qos_doc} - -The Quality-of-Service (QoS) scheduler performs egress-traffic management by -prioritizing the transmission of the packets of different type services and -subcribers based on the Service Level Agreements (SLAs). The QoS scheduler can -be enabled on one or more NIC output interfaces depending upon the -requirement. - - -## Overview - -The QoS schdeuler supports a number of scheduling and shaping levels which -construct hierarchical-tree. The first level in the hierarchy is port (i.e. -the physical interface) that constitutes the root node of the tree. The -subsequent level is subport which represents the group of the -users/subscribers. The individual user/subscriber is represented by the pipe -at the next level. Each user can have different traffic type based on the -criteria of specific loss rate, jitter, and latency. These traffic types are -represented at the traffic-class level in the form of different traffic- -classes. The last level contains number of queues which are grouped together -to host the packets of the specific class type traffic. - -The QoS scheduler implementation requires flow classification, enqueue and -dequeue operations. The flow classification is mandatory stage for HQoS where -incoming packets are classified by mapping the packet fields information to -5-tuple (HQoS subport, pipe, traffic class, queue within traffic class, and -color) and storing that information in mbuf sched field. The enqueue operation -uses this information to determine the queue for storing the packet, and at -this stage, if the specific queue is full, QoS drops the packet. The dequeue -operation consists of scheduling the packet based on its length and available -credits, and handing over the scheduled packet to the output interface. - -For more information on QoS Scheduler, please refer DPDK Programmer's Guide- -http://dpdk.org/doc/guides/prog_guide/qos_framework.html - - -### QoS Schdeuler Parameters - -Following illustrates the default HQoS configuration for each 10GbE output -port: - -Single subport (subport 0): - - Subport rate set to 100% of port rate - - Each of the 4 traffic classes has rate set to 100% of port rate - -4K pipes per subport 0 (pipes 0 .. 4095) with identical configuration: - - Pipe rate set to 1/4K of port rate - - Each of the 4 traffic classes has rate set to 100% of pipe rate - - Within each traffic class, the byte-level WRR weights for the 4 queues are set to 1:1:1:1 - - -#### Port configuration - -``` -port { - rate 1250000000 /* Assuming 10GbE port */ - frame_overhead 24 /* Overhead fields per Ethernet frame: - * 7B (Preamble) + - * 1B (Start of Frame Delimiter (SFD)) + - * 4B (Frame Check Sequence (FCS)) + - * 12B (Inter Frame Gap (IFG)) - */ - mtu 1522 /* Assuming Ethernet/IPv4 pkt (FCS not included) */ - n_subports_per_port 1 /* Number of subports per output interface */ - n_pipes_per_subport 4096 /* Number of pipes (users/subscribers) */ - queue_sizes 64 64 64 64 /* Packet queue size for each traffic class. - * All queues within the same pipe traffic class - * have the same size. Queues from different - * pipes serving the same traffic class have - * the same size. */ -} -``` - - -#### Subport configuration - -``` -subport 0 { - tb_rate 1250000000 /* Subport level token bucket rate (bytes per second) */ - tb_size 1000000 /* Subport level token bucket size (bytes) */ - tc0_rate 1250000000 /* Subport level token bucket rate for traffic class 0 (bytes per second) */ - tc1_rate 1250000000 /* Subport level token bucket rate for traffic class 1 (bytes per second) */ - tc2_rate 1250000000 /* Subport level token bucket rate for traffic class 2 (bytes per second) */ - tc3_rate 1250000000 /* Subport level token bucket rate for traffic class 3 (bytes per second) */ - tc_period 10 /* Time interval for refilling the token bucket associated with traffic class (Milliseconds) */ - pipe 0 4095 profile 0 /* pipes (users/subscribers) configured with pipe profile 0 */ -} -``` - - -#### Pipe configuration - -``` -pipe_profile 0 { - tb_rate 305175 /* Pipe level token bucket rate (bytes per second) */ - tb_size 1000000 /* Pipe level token bucket size (bytes) */ - tc0_rate 305175 /* Pipe level token bucket rate for traffic class 0 (bytes per second) */ - tc1_rate 305175 /* Pipe level token bucket rate for traffic class 1 (bytes per second) */ - tc2_rate 305175 /* Pipe level token bucket rate for traffic class 2 (bytes per second) */ - tc3_rate 305175 /* Pipe level token bucket rate for traffic class 3 (bytes per second) */ - tc_period 40 /* Time interval for refilling the token bucket associated with traffic class at pipe level (Milliseconds) */ - tc3_oversubscription_weight 1 /* Weight traffic class 3 oversubscription */ - tc0_wrr_weights 1 1 1 1 /* Pipe queues WRR weights for traffic class 0 */ - tc1_wrr_weights 1 1 1 1 /* Pipe queues WRR weights for traffic class 1 */ - tc2_wrr_weights 1 1 1 1 /* Pipe queues WRR weights for traffic class 2 */ - tc3_wrr_weights 1 1 1 1 /* Pipe queues WRR weights for traffic class 3 */ -} -``` - - -#### Random Early Detection (RED) parameters per traffic class and color (Green / Yellow / Red) - -``` -red { - tc0_wred_min 48 40 32 /* Minimum threshold for traffic class 0 queue (min_th) in number of packets */ - tc0_wred_max 64 64 64 /* Maximum threshold for traffic class 0 queue (max_th) in number of packets */ - tc0_wred_inv_prob 10 10 10 /* Inverse of packet marking probability for traffic class 0 queue (maxp = 1 / maxp_inv) */ - tc0_wred_weight 9 9 9 /* Traffic Class 0 queue weight */ - tc1_wred_min 48 40 32 /* Minimum threshold for traffic class 1 queue (min_th) in number of packets */ - tc1_wred_max 64 64 64 /* Maximum threshold for traffic class 1 queue (max_th) in number of packets */ - tc1_wred_inv_prob 10 10 10 /* Inverse of packet marking probability for traffic class 1 queue (maxp = 1 / maxp_inv) */ - tc1_wred_weight 9 9 9 /* Traffic Class 1 queue weight */ - tc2_wred_min 48 40 32 /* Minimum threshold for traffic class 2 queue (min_th) in number of packets */ - tc2_wred_max 64 64 64 /* Maximum threshold for traffic class 2 queue (max_th) in number of packets */ - tc2_wred_inv_prob 10 10 10 /* Inverse of packet marking probability for traffic class 2 queue (maxp = 1 / maxp_inv) */ - tc2_wred_weight 9 9 9 /* Traffic Class 2 queue weight */ - tc3_wred_min 48 40 32 /* Minimum threshold for traffic class 3 queue (min_th) in number of packets */ - tc3_wred_max 64 64 64 /* Maximum threshold for traffic class 3 queue (max_th) in number of packets */ - tc3_wred_inv_prob 10 10 10 /* Inverse of packet marking probability for traffic class 3 queue (maxp = 1 / maxp_inv) */ - tc3_wred_weight 9 9 9 /* Traffic Class 3 queue weight */ -} -``` - - -### DPDK QoS Scheduler Integration in VPP - -The Hierarchical Quaity-of-Service (HQoS) scheduler object could be seen as -part of the logical NIC output interface. To enable HQoS on specific output -interface, vpp startup.conf file has to be configured accordingly. The output -interface that requires HQoS, should have "hqos" parameter specified in dpdk -section. Another optional parameter "hqos-thread" has been defined which can -be used to associate the output interface with specific hqos thread. In cpu -section of the config file, "corelist-hqos-threads" is introduced to assign -logical cpu cores to run the HQoS threads. A HQoS thread can run multiple HQoS -objects each associated with different output interfaces. All worker threads -instead of writing packets to NIC TX queue directly, write the packets to a -software queues. The hqos_threads read the software queues, and enqueue the -packets to HQoS objects, as well as dequeue packets from HQOS objects and -write them to NIC output interfaces. The worker threads need to be able to -send the packets to any output interface, therefore, each HQoS object -associated with NIC output interface should have software queues equal to -worker threads count. - -Following illustrates the sample startup configuration file with 4x worker -threads feeding 2x hqos threads that handle each QoS scheduler for 1x output -interface. - -``` -dpdk { - socket-mem 16384,16384 - - dev 0000:02:00.0 { - num-rx-queues 2 - hqos - } - dev 0000:06:00.0 { - num-rx-queues 2 - hqos - } - - num-mbufs 1000000 -} - -cpu { - main-core 0 - corelist-workers 1, 2, 3, 4 - corelist-hqos-threads 5, 6 -} -``` - - -### QoS scheduler CLI Commands - -Each QoS scheduler instance is initialised with default parameters required to -configure hqos port, subport, pipe and queues. Some of the parameters can be -re-configured in run-time through CLI commands. - - -#### Configuration - -Following commands can be used to configure QoS scheduler parameters. - -The command below can be used to set the subport level parameters such as -token bucket rate (bytes per seconds), token bucket size (bytes), traffic -class rates (bytes per seconds) and token update period (Milliseconds). - -``` -set dpdk interface hqos subport <interface> subport <subport_id> [rate <n>] - [bktsize <n>] [tc0 <n>] [tc1 <n>] [tc2 <n>] [tc3 <n>] [period <n>] -``` - -For setting the pipe profile, following command can be used. - -``` -set dpdk interface hqos pipe <interface> subport <subport_id> pipe <pipe_id> - profile <profile_id> -``` - -To assign QoS scheduler instance to the specific thread, following command can -be used. - -``` -set dpdk interface hqos placement <interface> thread <n> -``` - -The command below is used to set the packet fields required for classifiying -the incoming packet. As a result of classification process, packet field -information will be mapped to 5 tuples (subport, pipe, traffic class, pipe, -color) and stored in packet mbuf. - -``` -set dpdk interface hqos pktfield <interface> id subport|pipe|tc offset <n> - mask <hex-mask> -``` - -The DSCP table entries used for idenfiying the traffic class and queue can be set using the command below; - -``` -set dpdk interface hqos tctbl <interface> entry <map_val> tc <tc_id> queue <queue_id> -``` - - -#### Show Command - -The QoS Scheduler configuration can displayed using the command below. - -``` - vpp# show dpdk interface hqos TenGigabitEthernet2/0/0 - Thread: - Input SWQ size = 4096 packets - Enqueue burst size = 256 packets - Dequeue burst size = 220 packets - Packet field 0: slab position = 0, slab bitmask = 0x0000000000000000 (subport) - Packet field 1: slab position = 40, slab bitmask = 0x0000000fff000000 (pipe) - Packet field 2: slab position = 8, slab bitmask = 0x00000000000000fc (tc) - Packet field 2 tc translation table: ([Mapped Value Range]: tc/queue tc/queue ...) - [ 0 .. 15]: 0/0 0/1 0/2 0/3 1/0 1/1 1/2 1/3 2/0 2/1 2/2 2/3 3/0 3/1 3/2 3/3 - [16 .. 31]: 0/0 0/1 0/2 0/3 1/0 1/1 1/2 1/3 2/0 2/1 2/2 2/3 3/0 3/1 3/2 3/3 - [32 .. 47]: 0/0 0/1 0/2 0/3 1/0 1/1 1/2 1/3 2/0 2/1 2/2 2/3 3/0 3/1 3/2 3/3 - [48 .. 63]: 0/0 0/1 0/2 0/3 1/0 1/1 1/2 1/3 2/0 2/1 2/2 2/3 3/0 3/1 3/2 3/3 - Port: - Rate = 1250000000 bytes/second - MTU = 1514 bytes - Frame overhead = 24 bytes - Number of subports = 1 - Number of pipes per subport = 4096 - Packet queue size: TC0 = 64, TC1 = 64, TC2 = 64, TC3 = 64 packets - Number of pipe profiles = 1 - Subport 0: - Rate = 120000000 bytes/second - Token bucket size = 1000000 bytes - Traffic class rate: TC0 = 120000000, TC1 = 120000000, TC2 = 120000000, TC3 = 120000000 bytes/second - TC period = 10 milliseconds - Pipe profile 0: - Rate = 305175 bytes/second - Token bucket size = 1000000 bytes - Traffic class rate: TC0 = 305175, TC1 = 305175, TC2 = 305175, TC3 = 305175 bytes/second - TC period = 40 milliseconds - TC0 WRR weights: Q0 = 1, Q1 = 1, Q2 = 1, Q3 = 1 - TC1 WRR weights: Q0 = 1, Q1 = 1, Q2 = 1, Q3 = 1 - TC2 WRR weights: Q0 = 1, Q1 = 1, Q2 = 1, Q3 = 1 - TC3 WRR weights: Q0 = 1, Q1 = 1, Q2 = 1, Q3 = 1 -``` - -The QoS Scheduler placement over the logical cpu cores can be displayed using -below command. - -``` - vpp# show dpdk interface hqos placement - Thread 5 (vpp_hqos-threads_0 at lcore 5): - TenGigabitEthernet2/0/0 queue 0 - Thread 6 (vpp_hqos-threads_1 at lcore 6): - TenGigabitEthernet4/0/1 queue 0 -``` - - -### QoS Scheduler Binary APIs - -This section explans the available binary APIs for configuring QoS scheduler -parameters in run-time. - -The following API can be used to set the pipe profile of a pipe that belongs -to a given subport: - -``` -sw_interface_set_dpdk_hqos_pipe rx <intfc> | sw_if_index <id> - subport <subport-id> pipe <pipe-id> profile <profile-id> -``` - -The data structures used for set the pipe profile parameter are as follows; - -``` - /** \\brief DPDK interface HQoS pipe profile set request - @param client_index - opaque cookie to identify the sender - @param context - sender context, to match reply w/ request - @param sw_if_index - the interface - @param subport - subport ID - @param pipe - pipe ID within its subport - @param profile - pipe profile ID - */ - define sw_interface_set_dpdk_hqos_pipe { - u32 client_index; - u32 context; - u32 sw_if_index; - u32 subport; - u32 pipe; - u32 profile; - }; - - /** \\brief DPDK interface HQoS pipe profile set reply - @param context - sender context, to match reply w/ request - @param retval - request return code - */ - define sw_interface_set_dpdk_hqos_pipe_reply { - u32 context; - i32 retval; - }; -``` - -The following API can be used to set the subport level parameters, for -example- token bucket rate (bytes per seconds), token bucket size (bytes), -traffic class rate (bytes per seconds) and tokens update period. - -``` -sw_interface_set_dpdk_hqos_subport rx <intfc> | sw_if_index <id> - subport <subport-id> [rate <n>] [bktsize <n>] - [tc0 <n>] [tc1 <n>] [tc2 <n>] [tc3 <n>] [period <n>] -``` - -The data structures used for set the subport level parameter are as follows; - -``` - /** \\brief DPDK interface HQoS subport parameters set request - @param client_index - opaque cookie to identify the sender - @param context - sender context, to match reply w/ request - @param sw_if_index - the interface - @param subport - subport ID - @param tb_rate - subport token bucket rate (measured in bytes/second) - @param tb_size - subport token bucket size (measured in credits) - @param tc_rate - subport traffic class 0 .. 3 rates (measured in bytes/second) - @param tc_period - enforcement period for rates (measured in milliseconds) - */ - define sw_interface_set_dpdk_hqos_subport { - u32 client_index; - u32 context; - u32 sw_if_index; - u32 subport; - u32 tb_rate; - u32 tb_size; - u32 tc_rate[4]; - u32 tc_period; - }; - - /** \\brief DPDK interface HQoS subport parameters set reply - @param context - sender context, to match reply w/ request - @param retval - request return code - */ - define sw_interface_set_dpdk_hqos_subport_reply { - u32 context; - i32 retval; - }; -``` - -The following API can be used set the DSCP table entry. The DSCP table have -64 entries to map the packet DSCP field onto traffic class and hqos input -queue. - -``` -sw_interface_set_dpdk_hqos_tctbl rx <intfc> | sw_if_index <id> - entry <n> tc <n> queue <n> -``` - -The data structures used for setting DSCP table entries are given below. - -``` - /** \\brief DPDK interface HQoS tctbl entry set request - @param client_index - opaque cookie to identify the sender - @param context - sender context, to match reply w/ request - @param sw_if_index - the interface - @param entry - entry index ID - @param tc - traffic class (0 .. 3) - @param queue - traffic class queue (0 .. 3) - */ - define sw_interface_set_dpdk_hqos_tctbl { - u32 client_index; - u32 context; - u32 sw_if_index; - u32 entry; - u32 tc; - u32 queue; - }; - - /** \\brief DPDK interface HQoS tctbl entry set reply - @param context - sender context, to match reply w/ request - @param retval - request return code - */ - define sw_interface_set_dpdk_hqos_tctbl_reply { - u32 context; - i32 retval; - }; -``` |