Are these settings related to Large Send Offload

Installing and Using OpenWrt
1

does anybody know if any of these settings are related to Large Send Offload (LSO)?

Features for eth2:
rx-checksumming: off
tx-checksumming: off
        tx-checksum-ipv4: off
        tx-checksum-ip-generic: off [fixed]
        tx-checksum-ipv6: off
        tx-checksum-fcoe-crc: off [fixed]
        tx-checksum-sctp: off [fixed]
scatter-gather: on
        tx-scatter-gather: on
        tx-scatter-gather-fraglist: off [fixed]
tcp-segmentation-offload: off
        tx-tcp-segmentation: off
        tx-tcp-ecn-segmentation: off [fixed]
        tx-tcp-mangleid-segmentation: off
        tx-tcp6-segmentation: off
generic-segmentation-offload: off
generic-receive-offload: off
large-receive-offload: off [fixed]
rx-vlan-offload: on
tx-vlan-offload: on
ntuple-filters: off [fixed]
receive-hashing: on
highdma: on [fixed]
rx-vlan-filter: off [fixed]
vlan-challenged: off [fixed]
tx-lockless: off [fixed]
netns-local: off [fixed]
tx-gso-robust: off [fixed]
tx-fcoe-segmentation: off [fixed]
tx-gre-segmentation: off [fixed]
tx-gre-csum-segmentation: off [fixed]
tx-ipxip4-segmentation: off [fixed]
tx-ipxip6-segmentation: off [fixed]
tx-udp_tnl-segmentation: off [fixed]
tx-udp_tnl-csum-segmentation: off [fixed]
tx-gso-partial: off [fixed]
tx-tunnel-remcsum-segmentation: off [fixed]
tx-sctp-segmentation: off [fixed]
tx-esp-segmentation: off [fixed]
tx-udp-segmentation: off [fixed]
tx-gso-list: off [fixed]
fcoe-mtu: off [fixed]
tx-nocache-copy: off
loopback: off [fixed]
rx-fcs: off
rx-all: off
tx-vlan-stag-hw-insert: off [fixed]
rx-vlan-stag-hw-parse: off [fixed]
rx-vlan-stag-filter: off [fixed]
l2-fwd-offload: off [fixed]
hw-tc-offload: off [fixed]
esp-hw-offload: off [fixed]
esp-tx-csum-hw-offload: off [fixed]
rx-udp_tunnel-port-offload: off [fixed]
tls-hw-tx-offload: off [fixed]
tls-hw-rx-offload: off [fixed]
rx-gro-hw: off [fixed]
tls-hw-record: off [fixed]
rx-gro-list: off
macsec-hw-offload: off [fixed]
rx-udp-gro-forwarding: off
hsr-tag-ins-offload: off [fixed]
hsr-tag-rm-offload: off [fixed]
hsr-fwd-offload: off [fixed]
hsr-dup-offload: off [fixed]
2

Yes, some of those are related.

If further assistance is needed, it might help if you explained why you installed a non-default software to provide output for this particular inquiry.

3

I think these would be related to LSO (which IIRC means the NIC/driver does the segmentation), while these

are related to Linux "software" segmentation where the Linux stack does the segmentation.

That said, often that is something where googling can help a lot.

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4

It somewhat breaks end to end integrity of packe%s being routed. Unless there are significant performance impact router should not re-fragment packets.

5

For TCP? TCP being a stream protocol no real reliance should be placed on packet boundaries...

There are significant performance impacts, if say 10 fullMTU packets are merged, then you only have 1/210 of the per packet cost, e.g. for forwarding lookups and similar.

6

I did try to search around but I was getting mixed answers. Some said it was GSO and GRO paired with TSO that is the essence of LSO then I was seeing tx-udp-segmentation is apart of it but TSO seems to be correct as I read both functions of LSO and TSO and they both seem similar. Both help break down large packets if I can remember what I read.

7

What do you mean? It’s openwrt 24.10 release. If you are wondering why most of them are off. It’s because I was messing around with the settings

8

I mean the command you executed is not on a 24.10 default firmware (i.e., I'm guessing you customized it or installed the package for ethtool). That's all.

I was inquiring why you installed the package to mess around with them in the first place (e.g., were you experiencing some issue prompting you to install).

9

But IMHO ethtool-full should be in the default set...

10

I just used ethtool -k to find these settings

11

Yes I was experiencing dropped packets but I figured out how to fix that. Just wanted to tune around with some offload settings and tests latency differences with on vs off. Usually I get better tests with large send offload off on windows so I wanted to see if openwrt kernel has LSO.

12

What's the output of ubus call system board

13

So the version I’m using is the first official release of openwrt which is 24.10 on NanoPi R6S

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14

Can’t quite input the command as I’m not on my home network right now.

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