38. Fortville RSS - Configuring Hash Function Tests¶

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

38.1. 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.

38.1.1. 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.

The receive packet is parsed into the header fields used by the hash operation (such as IP addresses, TCP port, etc.)
A hash calculation is performed. The Fortville supports four hash function: Toeplitz, simple XOR and their Symmetric RSS.
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.
There are four cases to test the four hash function.

38.2. Test Case: test_toeplitz¶

38.2.1. Testpmd configuration - 16 RX/TX queues per port¶

set up testpmd with fortville NICs:

./testpmd -c fffff -n %d -- -i --coremask=0xffffe --rxq=16 --txq=16

Reta Configuration. 128 reta entries configuration:

testpmd command: port config 0 rss reta (hash_index,queue_id)

PMD fwd only receive the packets:
```
testpmd command: set fwd rxonly
```
rss received package type configuration two received packet types configuration:
```
testpmd command: port config 0 rss ip/udp
```
verbose configuration:
```
testpmd command: set verbose 8
```
set hash functions, can choose symmetric or not, choose port and packet type:
```
set_hash_function 0 toeplitz
```
start packet receive:
```
testpmd command: start
```

38.2.2. tester Configuration¶

set up scapy
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="192.168.0.4", dst="192.168.0.5")], iface="eth3")
```

38.2.3. test result¶

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

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

38.3. Test Case: test_toeplitz_symmetric¶

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

set_hash_function 0 toeplitz
set_sym_hash_ena_per_port 0 enable
set_sym_hash_ena_per_pctype 0 35 enable

And send packets with the same flow in different direction:

sendp([Ether(dst="90:e2:ba:36:99:3c")/IP(src="192.168.0.4", dst="192.168.0.5")], iface="eth3")
sendp([Ether(dst="90:e2:ba:36:99:3c")/IP(src="192.168.0.5", dst="192.168.0.4")], iface="eth3")

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

38.4. Test Case: test_simple¶

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

38.5. Test Case: test_simple_symmetric¶

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

38.6. Test Case: test_dynamic_rss_bond_config¶

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

set up testpmd with fortville NICs:

./testpmd -c f -n 4 -- -i --portmask 0x3 --tx-offloads=0x8fff

create bond device with mode 3:
```
create bonded device 3 0
```

add slave to bond device:

add bonding slave 0 2
add bonding slave 1 2

get default hash algorithm on slave:

get_hash_global_config 0
get_hash_global_config 1

set hash algorithm on slave 0:

set_hash_global_config 0 simple_xor ipv4-other enable

get hash algorithm on slave 0 and 1:

get_hash_global_config 0
get_hash_global_config 1

check slave 0 and 1 use same hash algorithm