137. RSS Key Update Tests¶

This document provides test plan to configure Receive Side Scaling (RSS) hash key. This test case use similar testing method in `pmdrss_hash`. Verify setting a new hash key will result a change in packets queue destination.

138. Prerequisites¶

Assuming that ports 0 and 1 of the test target are directly connected to the traffic generator and hash function Toeplitz is supported.

138.1. Test Case: test_set_hash_key_toeplitz¶

Launch the testpmd application with the following arguments:

./<build_target>/app/dpdk-testpmd -c ffffff -n 4 -- -i --rxq=16 --txq=16

PMD fwd only receive the packets:
```
testpmd> set fwd rxonly
```
Set port verbosity to 8:
```
testpmd> set verbose 8
```
Configure a RETA table with 512 or 128 entries to store queue:
```
testpmd> port config 0 rss reta (hash_index,queue_id)
```

Set hash function, symmetric, port and packet type:

testpmd> flow create 0 ingress pattern eth / ipv4 / udp / end actions rss types ipv4-udp end queues end func toeplitz / end
testpmd> flow create 0 ingress pattern eth / ipv4 / tcp / end actions rss types ipv4-tcp end queues end func toeplitz / end
types in pattern must match rss types.

Configure RSS hash:

testpmd> port config all rss <udp|tcp>
verify "error" not in out

Send packet and print the hash value and queue id of every packet. Then use the hash value % the table size to find expected queue id. Make sure the expected queue and the destination queue id are the same.
Check RSS enable/disable and types of RSS hash function for each port:
```
testpmd> show port <port-id> rss-hash
```
RSS is on by default, unless `--disable-rss` flag is apply.

Configure new RSS hash key:

testpmd> port config <port_id> rss-hash-key <ipv4|ipv4-frag|\
              ipv4-tcp|ipv4-udp|ipv4-sctp|ipv4-other|\
              ipv6|ipv6-frag|ipv6-tcp|ipv6-udp|ipv6-sctp|\
              ipv6-other|l2-payload|ipv6-ex|ipv6-tcp-ex|\
              ipv6-udp-ex> <string of hex digits>

Send packet and print the hash value again to check if they have the same hash value and destination queue id.

138.2. Test Case: test_set_hash_key_toeplitz_symmetric¶

Same steps as the “test_set_hash_key_toeplitz” test case. When set hash function you will need to add:

testpmd> flow create 0 ingress pattern eth / ipv4 / tcp / end actions rss types ipv4-tcp end queues end func symmetric_toeplitz queues end / end

Then send in packet as normal.

138.3. Test Case: test_set_hash_key_long_short¶

Check hash key size is supported in “show port info”
Check RSS is enable

Configure RSS hash key in testpmd with longer/normal/shorter hash key:

testpmd> port config <port_id> rss-hash-key <ipv4|ipv4-frag|\
              ipv4-tcp|ipv4-udp|ipv4-sctp|ipv4-other|\
              ipv6|ipv6-frag|ipv6-tcp|ipv6-udp|ipv6-sctp|\
              ipv6-other|l2-payload|ipv6-ex|ipv6-tcp-ex|\
              ipv6-udp-ex> <string of hex digits>

Display updated key and compare it with the original key:
```
testpmd> show port <port-id> rss-hash key
```