Am Mittwoch, dem 02.04.2025 um 23:12 +0200 schrieb Markus Fohrer: > When running on a host system equipped with a Broadcom NetXtreme-E > (bnxt_en) NIC and AMD EPYC CPUs, the network throughput in the guest > drops to 100–200 KB/s. The same guest configuration performs normally > (~100 MB/s) when using kernel 6.8.0 or when the VM is moved to a host > with Intel NICs. Hi, as I am affected too, here is the link to the Ubuntu issue, just in case someone wants to have a look: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2098961 We're seeing lots of those in dmesg output: [ 561.505323] net_ratelimit: 1396 callbacks suppressed [ 561.505339] ens18: bad gso: type: 4, size: 1448 [ 561.505343] ens18: bad gso: type: 4, size: 1448 [ 561.507270] ens18: bad gso: type: 4, size: 1448 [ 561.508257] ens18: bad gso: type: 4, size: 1448 [ 561.511432] ens18: bad gso: type: 4, size: 1448 [ 561.511452] ens18: bad gso: type: 4, size: 1448 [ 561.514719] ens18: bad gso: type: 4, size: 1448 [ 561.514966] ens18: bad gso: type: 4, size: 1448 [ 561.518553] ens18: bad gso: type: 4, size: 1448 [ 561.518781] ens18: bad gso: type: 4, size: 1448 [ 566.506044] net_ratelimit: 1363 callbacks suppressed And another interesting thing we observed - at least in our environment - that we can trigger that regression only with IPv4 traffic (bad performance and lots of bad gso messages) - if we only use IPv6, it does work (good performance and not one bad gso message). kind regards Torsten
