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Chapter 7. Testing InfiniBand networks

This section provides procedures how to test InfiniBand networks.

7.1. Testing early InfiniBand RDMA operations

This section describes how to test InfiniBand remote direct memory access (RDMA) operations.

Note

This section applies only to InfiniBand devices. If you use IP-based devices such as Internet Wide-area Remote Protocol(iWARP) or RDMA over Converged Ethernet (RoCE) or InfiniBand over Ethernet (IBoE) devices, see:

Prerequisites

  • The rdma service is configured
  • The libibverbs-utils and infiniband-diags packages are installed

Procedure

  1. List the available InfiniBand devices:

    # ibv_devices
    
        device                 node GUID
        ------              ----------------
        mlx4_0              0002c903003178f0
        mlx4_1              f4521403007bcba0
  2. To display the information of the mlx4_1 device:

    # ibv_devinfo -d mlx4_1
    
    hca_id: mlx4_1
         transport:                  InfiniBand (0)
         fw_ver:                     2.30.8000
         node_guid:                  f452:1403:007b:cba0
         sys_image_guid:             f452:1403:007b:cba3
         vendor_id:                  0x02c9
         vendor_part_id:             4099
         hw_ver:                     0x0
         board_id:                   MT_1090120019
         phys_port_cnt:              2
              port:   1
                    state:              PORT_ACTIVE (4)
                    max_mtu:            4096 (5)
                    active_mtu:         2048 (4)
                    sm_lid:             2
                    port_lid:           2
                    port_lmc:           0x01
                    link_layer:         InfiniBand
    
              port:   2
                    state:              PORT_ACTIVE (4)
                    max_mtu:            4096 (5)
                    active_mtu:         4096 (5)
                    sm_lid:             0
                    port_lid:           0
                    port_lmc:           0x00
                    link_layer:         Ethernet
  3. To display the status of the mlx4_1 device:

    # ibstat mlx4_1
    
    CA 'mlx4_1'
         CA type: MT4099
         Number of ports: 2
         Firmware version: 2.30.8000
         Hardware version: 0
         Node GUID: 0xf4521403007bcba0
         System image GUID: 0xf4521403007bcba3
         Port 1:
               State: Active
               Physical state: LinkUp
               Rate: 56
               Base lid: 2
               LMC: 1
               SM lid: 2
               Capability mask: 0x0251486a
               Port GUID: 0xf4521403007bcba1
               Link layer: InfiniBand
         Port 2:
               State: Active
               Physical state: LinkUp
               Rate: 40
               Base lid: 0
               LMC: 0
               SM lid: 0
               Capability mask: 0x04010000
               Port GUID: 0xf65214fffe7bcba2
               Link layer: Ethernet
  4. The ibping utility pings an InfiniBand address and runs as a client/server.

    1. To start server mode on a host, use the -S parameter on port number -P with -C InfiniBand certificate authority (CA) name:

      # ibping -S -C mlx4_1 -P 1
    2. To start client mode on another host, send some packets -c on port number -P using -C InfiniBand certificate authority (CA) name with -L Local Identifier (LID):

      # ibping -c 50 -C mlx4_0 -P 1 -L 2

Additional resources

  • ibping(8) man page

7.2. Testing an IPoIB using the ping utility

After you configured IP over InfiniBand (IPoIB), use the ping utility to send ICMP packets to test the IPoIB connection.

Prerequisites

  • The two RDMA hosts are connected in the same InfiniBand fabric with RDMA ports
  • The IPoIB interfaces in both hosts are configured with IP addresses within the same subnet

Procedure

  • Use the ping utility to send five ICMP packets to the remote host’s InfiniBand adapter:

    # ping -c5 192.0.2.1

7.3. Testing an RDMA network using qperf after IPoIB is configured

The qperf utility measures RDMA and IP performance between two nodes in terms of bandwidth, latency, and CPU utilization.

Prerequisites

  • The qperf package is installed on both hosts
  • IPoIB is configured on both hosts

Procedure

  1. Start qperf on one of the hosts without any options to act as a server:

    # qperf
  2. Use the following commands on the client. The commands use port 1 of the mlx4_0 host channel adapter in the client to connect to IP address 192.0.2.1 assigned to the InfiniBand adapter in the server.

    1. To display the configuration:

      # qperf -v -i mlx4_0:1 192.0.2.1 conf
      
      conf:
          loc_node   =  rdma-dev-01.lab.bos.redhat.com
          loc_cpu    =  12 Cores: Mixed CPUs
          loc_os     =  Linux 4.18.0-187.el8.x86_64
          loc_qperf  =  0.4.11
          rem_node   =  rdma-dev-00.lab.bos.redhat.com
          rem_cpu    =  12 Cores: Mixed CPUs
          rem_os     =  Linux 4.18.0-187.el8.x86_64
          rem_qperf  =  0.4.11
    2. To display the Reliable Connection (RC) streaming two-way bandwidth:

      # qperf -v -i mlx4_0:1 192.0.2.1 rc_bi_bw
      
      rc_bi_bw:
          bw             =  10.7 GB/sec
          msg_rate       =   163 K/sec
          loc_id         =  mlx4_0
          rem_id         =  mlx4_0:1
          loc_cpus_used  =    65 % cpus
          rem_cpus_used  =    62 % cpus
    3. To display the RC streaming one-way bandwidth:

      # qperf -v -i mlx4_0:1 192.0.2.1 rc_bw
      
      rc_bw:
          bw              =  6.19 GB/sec
          msg_rate        =  94.4 K/sec
          loc_id          =  mlx4_0
          rem_id          =  mlx4_0:1
          send_cost       =  63.5 ms/GB
          recv_cost       =    63 ms/GB
          send_cpus_used  =  39.5 % cpus
          recv_cpus_used  =    39 % cpus

Additional resources

  • qperf(1) man page