105. Fortville RSS - Configuring Hash Function Tests

This document provides test plan for testing the function of Fortville: Support configuring hash functions.

105.1. Prerequisites

  • 2x Intel® 82599 (Niantic) NICs (2x 10GbE full duplex optical ports per NIC)
  • 1x Fortville_eagle NIC (4x 10G)
  • 1x Fortville_spirit NIC (2x 40G)
  • 2x Fortville_spirit_single NIC (1x 40G)

The four ports of the 82599 connect to the Fortville_eagle; The two ports of Fortville_spirit connect to Fortville_spirit_single. The three kinds of NICs are the target NICs. the connected NICs can send packets to these three NICs using scapy.

105.1.1. Network Traffic

The RSS feature is designed to improve networking performance by load balancing the packets received from a NIC port to multiple NIC RX queues, with each queue handled by a different logical core.

  1. The receive packet is parsed into the header fields used by the hash operation (such as IP addresses, TCP port, etc.)
  2. A hash calculation is performed. The Fortville supports four hash function: Toeplitz, simple XOR and their Symmetric RSS.
  3. The seven LSBs of the hash result are used as an index into a 128/512 entry ‘redirection table’. Each entry provides a 4-bit RSS output index.
  4. There are four cases to test the four hash function.

105.2. Test Case: test_toeplitz

105.2.1. Testpmd configuration - 16 RX/TX queues per port

  1. set up testpmd with fortville NICs:

    ./testpmd -c fffff -n %d -- -i --coremask=0xffffe --rxq=16 --txq=16
  2. Reta Configuration. 128 reta entries configuration:

    testpmd command: port config 0 rss reta (hash_index,queue_id)
  3. PMD fwd only receive the packets:

    testpmd command: set fwd rxonly
  4. rss received package type configuration two received packet types configuration:

    testpmd command: port config 0 rss ip/udp
  5. verbose configuration:

    testpmd command: set verbose 8
  6. set hash functions, can choose symmetric or not, choose port and packet type:

    testpmd command: set_hash_global_config 0 toeplitz ipv4-other enable
  7. start packet receive:

    testpmd command: start

105.2.2. tester Configuration

  1. set up scapy

  2. send packets with different type ipv4/ipv4 with tcp/ipv4 with udp/ ipv6/ipv6 with tcp/ipv6 with udp:

    sendp([Ether(dst="90:e2:ba:36:99:3c")/IP(src="", dst="")], iface="eth3")

105.2.3. test result

The testpmd will print the hash value and actual queue of every packet.

  1. Calculate the queue id: hash value%128or512, then refer to the redirection table to get the theoretical queue id.
  2. Compare the theoretical queue id with the actual queue id.

105.3. Test Case: test_toeplitz_symmetric

The same with the above steps, pay attention to “set hash function”, should use:

set_hash_global_config 0 toeplitz ipv4-other enable
set_sym_hash_ena_per_port 0 enable

And send packets with the same flow in different direction:

sendp([Ether(dst="90:e2:ba:36:99:3c")/IP(src="", dst="")], iface="eth3")
sendp([Ether(dst="90:e2:ba:36:99:3c")/IP(src="", dst="")], iface="eth3")

And the hash value and queue should be the same for these two flow .

105.4. Test Case: test_simple

The same as the above test case “test_toeplitz”. Just pay attention to set the hash function to “simple xor”

105.5. Test Case: test_simple_symmetric

The same as the above test case “test_toeplitz_symmetric”. Just pay attention to set the hash function to “simple xor”

105.6. Test Case: test_dynamic_rss_bond_config

This case test bond slaves will auto sync rss hash config, it only support by fortville.

  1. set up testpmd with fortville NICs:

    ./testpmd -c f -n 4 -- -i
  2. create bond device with mode 3:

    create bonded device 3 0
  3. add slave to bond device:

    add bonding slave 0 2
    add bonding slave 1 2
  4. get default hash algorithm on slave:

    get_hash_global_config 0
    get_hash_global_config 1
  5. set hash algorithm on slave 0:

    set_hash_global_config 0 simple_xor ipv4-other enable
  6. get hash algorithm on slave 0 and 1:

    get_hash_global_config 0
    get_hash_global_config 1
  7. check slave 0 and 1 use same hash algorithm