[tor-relays] Overload (dropped ntor) due to DDoS??

[Richard Menedetter]

Hi All

I have a non exit relay running on a root server (4 AMD Epyc cores, 8 GB RAM, 2.5 GBit/s Ethernet)
I have limited tor to numcpus 2, relaybandwidthburst 15 MB, hardwareaccel 1, maxadvertisedbandwidth 10 MB, maxmeminqueues 3GB

Usually it takes less than 1 CPU core, and like 1 GB of RAM.
But recently my relay is foten shown as obverloaded.
I have these LOG entries:
Tor[814]: General overload -> Ntor dropped (290376) fraction 5.3451% is above threshold of 0.5000%

Is this due to DDoS attacks or a misconfigration on my side?
Is there something that I can do to aleviate this issue?

CU, Ricsi