Hi,
Ive been looking into the MTU terminology and would just like to clarify
some naming conventions and doc strings.
On 7/26/24 15:13, Nicholas Pratte wrote:
<snip>
+IP_HEADER_LEN = 20
+ETHER_STANDARD_FRAME = 1500
+ETHER_JUMBO_FRAME_MTU = 9000
For these constants, I am confused why one is "FRAME" and the other is
"MTU". The value of 'ETHER_STANDARD_FRAME' is 1500 (the standard MTU
size), it would make sense to rename it to 'ETHER_STANDARD_MTU', to keep
naming consistent.
If the value was 1518 instead of 1500, then `ETHER_STANDARD_FRAME` would
be appropriate.
<snip>
+ def test_jumboframes_normal_nojumbo(self) -> None:
+ """Assess the boundaries of packets sent less than or equal to the
standard MTU length.
+
+ PMDs are set to the standard MTU length of 1518 to assess behavior of
sent packets less than
+ or equal to this size. Sends two packets: one that is less than 1518
bytes, and another that
+ is equal to 1518 bytes. The test case expects to receive both packets.
+
+ Test:
+ Start testpmd and send packets of sizes 1517 and 1518.
+ """
+ with TestPmdShell(
+ self.sut_node, tx_offloads=0x8000, mbuf_size=[9200], mbcache=200
+ ) as testpmd:
+ testpmd.configure_port_mtu_all(ETHER_STANDARD_FRAME)
+ testpmd.start()
Renaming 'ETHER_STANDARD_FRAME' to 'ETHER_STANDARD_MTU' would reduce
confusion here too.
e.g.
`testpmd.configure_port_mtu_all(ETHER_STANDARD_MTU)`
Additionally, you state you are sending packets of sizes 1517 and 1518.
but you then call:
`self.send_packet_and_verify(ETHER_STANDARD_FRAME - 5)`
`self.send_packet_and_verify(ETHER_STANDARD_FRAME)`
Calculating to:
`self.send_packet_and_verify(1495)`
`self.send_packet_and_verify(1500)`
Which is confusing.
I believe this is because you are accounting for the 4 bytes of VLAN's
in your calculations, but you might want to explain this.
Overall very solid and clean test suite, just wanted to get
clarification on a few areas 🙂.
Alex
