@rpycroft That’s the confirmation I needed, thank you. 1.2 to 6.5 GB/min is
the fix working. The change is merged now, so it’ll be in the next kernel
release rather than something you have to keep hand-installing.
Two corrections from my end.
First, tx checksumming: ko was never broken. That line is about jumbo frames –
it’s the driver saying this chip can’t do TX checksum offload if you enable
jumbo, and at a normal 1500 MTU it never applies. It’s printed based on the
chip model alone, so you’ll still see it on the new kernel. Don’t let it worry
you when you spot it again. Your ethtool output was very likely the same before
the swap; there was nothing to fix there.
Second, I got two details wrong in the setpci commands I posted. My apologies.
The write should be masked so it only touches the two ASPM bits – as I wrote
it, it would have cleared the whole Link Control register, including the common
clock configuration, which you don’t want to disturb on a live link. And the
order was backwards: the spec wants L1 switched off at the NIC before the root
port, not the other way round.
Reading the current state (this part was fine):
setpci -s 02:00.0 CAP_EXP+10.w
setpci -s 00:1c.5 CAP_EXP+10.w
Only the last hex digit matters:
0 4 8 C -> ASPM off
1 5 9 D -> L0s
2 6 A E -> L1
3 7 B F -> L0s + L1
And clearing it, NIC first, masked to the ASPM bits:
setpci -s 02:00.0 CAP_EXP+10.w=0000:0003
setpci -s 00:1c.5 CAP_EXP+10.w=0000:0003
If you did already run the originals, nothing you’ve reported suggests any harm
came of it, and a reboot clears the lot either way.
No pressure on this next bit at all – the fix is confirmed and merged, and
this doesn’t gate anything. But if you ever have one of those 3070s spare, the
read-only pair above run once under UEFI and once under legacy would tell us
why the two differ. My theory is the Dell firmware enables L1 on the UEFI
path and leaves it off under CSM, which would explain everything you saw, but
that’s still me inferring rather than knowing. Genuinely optional – if it’s
easy, great, and if not, don’t spend your time on it.
Thanks again for testing this so quickly.
