[dpdk-dev] Unable to get RSS to work in testpmd and load balancing question

[Daniel Kan]

Thanks, Sy Jong. I couldn’t reproduce your outcome on dpdk 1.5.1 with ixgbe. As I sent in the earlier email, rxmode.mq_mode is defaulted to 0 (i.e. ETH_MQ_RX_NONE); it should be set to ETH_MQ_RX_RSS.

Dan

On Jan 9, 2014, at 6:07 PM, Choi, Sy Jong <sy.jong.choi at intel.com> wrote:

> 
> Hi Dan,
> 
> I have tested with 6 flows with identical ip address, but varies UDP port number. I can see both queues with traffic.
> Using the following command:-
> sudo ./app/testpmd -c 0x1f -n 4 -- -i -rss-udp --portmask=0x03 --nb-cores=4 --rxq=2 --txq=2
> 
> 
> I have started with RSS IPv4, which is enabled by default.
> The critical part is the traffic, since I only 2 queues, I am sending 6 flows with different IP addresses in order to see the flow got distributed evenly. Or else you might see only 1 queues if you have 2 flows they might load to a single queue only.  
> 
> My Command:-
> sudo ./app/testpmd -c 0x1f -n 4 -- -i --portmask=0x03 --nb-cores=4 --rxq=2 --txq=2
> -	Using 4 cores
> -	Rxq = 2 for each port, so 4 queues to 4 cores.
> 
> 
> 
> testpmd> show port stats all
> 
>   ######################## NIC statistics for port 0  ########################
>   RX-packets:              6306519648    RX-errors:  757945685    RX-bytes: 309383840254
>   TX-packets:               132592678    TX-errors:          0    TX-bytes: 8485925376
> 
>   Stats reg  0 RX-packets: 2556150208    RX-errors:          0    RX-bytes: 116477417471
>   Stats reg  1 RX-packets: 3750369440    RX-errors:          0    RX-bytes: 192906422783
>   Stats reg  2 RX-packets:          0    RX-errors:          0    RX-bytes:          0
> .
> .
> .
>   Stats reg 15 RX-packets:          0    RX-errors:          0    RX-bytes:          0
>   ############################################################################
> 
>   ######################## NIC statistics for port 1  ########################
>   RX-packets:               132594048    RX-errors:   13825889    RX-bytes: 8486020288
>   TX-packets:              6306522739    TX-errors:          0    TX-bytes: 231983528894
> 
>   Stats reg  0 RX-packets:   83615783    RX-errors:          0    RX-bytes: 5351410624
>   Stats reg  1 RX-packets:   48978265    RX-errors:          0    RX-bytes: 3134609664
>   Stats reg  2 RX-packets:          0    RX-errors:          0    RX-bytes:          0
> .
> .
> .
>   Stats reg 15 RX-packets:          0    RX-errors:          0    RX-bytes:          0
>   ############################################################################
> testpmd>
> 
> 
> 
> 
> My Command:-
> sudo ./app/testpmd -c 0x1f -n 4 -- -i --portmask=0x03 --nb-cores=4 --rxq=2 --txq=2
> - Using 4 cores
> - Rxq = 2 for each port, so 4 queues to 4 cores.
> 
> I use this command to map the queue statistic.
> testpmd> set stat_qmap rx 0 0 0
> testpmd> set stat_qmap rx 0 1 1
> testpmd> set stat_qmap rx 1 0 0
> testpmd> set stat_qmap rx 1 1 1
> testpmd> start
>   io packet forwarding - CRC stripping disabled - packets/burst=16
>   nb forwarding cores=2 - nb forwarding ports=2
>   RX queues=2 - RX desc=128 - RX free threshold=0
>   RX threshold registers: pthresh=8 hthresh=8 wthresh=4
>   TX queues=2 - TX desc=512 - TX free threshold=0
>   TX threshold registers: pthresh=36 hthresh=0 wthresh=0
>   TX RS bit threshold=0 - TXQ flags=0x0
> 
> testpmd> show port stats all
> 
> 
> 
> Regards,
> Choi, Sy Jong
> Platform Application Engineer
> 
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Dan Kan
> Sent: Wednesday, January 08, 2014 3:25 PM
> To: dev at dpdk.org
> Subject: [dpdk-dev] Unable to get RSS to work in testpmd and load balancing question
> 
> I'm evaluating DPDK using dpdk-1.5.1r1. I have been playing around with the test-pmd sample app. I'm having a hard time to get RSS to work. I have a 2-port 82599 Intel X540-DA2 NIC. I'm running the following command to start the app.
> 
> sudo ./testpmd -c 0x1f -n 2 -- -i --portmask=0x3 --nb-cores=4 --rxq=4
> --txq=4
> 
> I have a packet generator that sends udp packets with various src IP.
> According testpmd, I'm only receiving packets in port 0's queue 0. Packets are not going into any other queues. I have attached the output from testpmd.
> 
> 
>  ------- Forward Stats for RX Port= 0/Queue= 0 -> TX Port= 1/Queue= 0
> -------
>  RX-packets: 1000000        TX-packets: 1000000        TX-dropped:
> 0
>  ---------------------- Forward statistics for port 0
> ----------------------
>  RX-packets: 1000000        RX-dropped: 0             RX-total: 1000000
>  TX-packets: 0              TX-dropped: 0             TX-total: 0
> 
> ----------------------------------------------------------------------------
> 
>  ---------------------- Forward statistics for port 1
> ----------------------
>  RX-packets: 0              RX-dropped: 0             RX-total: 0
>  TX-packets: 1000000        TX-dropped: 0             TX-total: 1000000
> 
> ----------------------------------------------------------------------------
> 
>  +++++++++++++++ Accumulated forward statistics for all
> ports+++++++++++++++
>  RX-packets: 1000000        RX-dropped: 0             RX-total: 1000000
>  TX-packets: 1000000        TX-dropped: 0             TX-total: 1000000
> 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 
> On a separate note, I also find that the CPU utilization using 1 forwarding core for 2 ports seems to be better (in the aggregate sense) than using 2 forwarding cores for 2 ports. Running at 10gbps line rate of pktlen=400, with 1 core, the core's utilization is 40%. With 2 cores, each core's utilization would 30%, giving an aggregate of 60%.
> 
> I have a use case of only doing rxonly packet processing. From my initial test, it seems that it's more efficient to have a single core read packets from both ports, and distribute the packet using rte_ring instead of having each core read from its port. The rte_eth_rx operations appear to be much CPU intensive than rte_ring_dequeue operations.
> 
> Thanks in advance.
> 
> Dan
>