https://bugzilla.kernel.org/show_bug.cgi?id=219129 Bug ID: 219129 Summary: virtio net performance degradation between Windows and Linux guest in kernel 6.10.3 Product: Virtualization Version: unspecified Hardware: All OS: Linux Status: NEW Severity: normal Priority: P3 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: anton.wd@xxxxxxxxx Regression: No After kernel upgrade from 6.10.2 to 6.10.3 network performance has become very low between Windows and Linux guest. Steps to reproduce: MTU 9000 for all adapters and bridge (Jumbo frame 9014 in Windows) KVM host, qemu 9.0.2, bridge (e.g. br0) Linux guest, virtio net adapter bridged to host br0, address e.g. 192.168.0.1 Windows 11 guest, virtio net adapter, bridged to host br0, address e.g. 192.168.0.2 When accessing Linux guest from Windows 11 and if kvm host OR Linux guest has kernel version 6.10.3 then network performance is poor. iperf3 for example: $ iperf3.exe --client 192.168.0.1 Connecting to host 192.168.0.1, port 5201 [ 5] local 192.168.0.2 port 49849 connected to 192.168.0.1 port 5201 [ ID] Interval Transfer Bitrate [ 5] 0.00-1.01 sec 256 KBytes 2.08 Mbits/sec [ 5] 1.01-2.01 sec 128 KBytes 1.04 Mbits/sec [ 5] 2.01-3.01 sec 0.00 Bytes 0.00 bits/sec [ 5] 3.01-4.01 sec 128 KBytes 1.05 Mbits/sec [ 5] 4.01-5.00 sec 0.00 Bytes 0.00 bits/sec [ 5] 5.00-6.01 sec 0.00 Bytes 0.00 bits/sec [ 5] 6.01-7.01 sec 0.00 Bytes 0.00 bits/sec [ 5] 7.01-8.01 sec 128 KBytes 1.05 Mbits/sec [ 5] 8.01-9.01 sec 0.00 Bytes 0.00 bits/sec [ 5] 9.01-10.01 sec 0.00 Bytes 0.00 bits/sec - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate [ 5] 0.00-10.01 sec 640 KBytes 524 Kbits/sec sender [ 5] 0.00-10.02 sec 384 KBytes 314 Kbits/sec receiver iperf Done. If kvm host AND Linux guest has kernel version 6.10.2 then performance seems ok $ iperf3.exe --client 192.168.0.1 Connecting to host 192.168.0.1, port 5201 [ 5] local 192.168.0.2 port 50092 connected to 192.168.0.1 port 5201 [ ID] Interval Transfer Bitrate [ 5] 0.00-1.01 sec 3.86 GBytes 33.0 Gbits/sec [ 5] 1.01-2.01 sec 3.78 GBytes 32.4 Gbits/sec [ 5] 2.01-3.02 sec 3.72 GBytes 31.6 Gbits/sec [ 5] 3.02-4.01 sec 3.75 GBytes 32.2 Gbits/sec [ 5] 4.01-5.01 sec 3.80 GBytes 32.8 Gbits/sec [ 5] 5.01-6.01 sec 3.64 GBytes 31.3 Gbits/sec [ 5] 6.01-7.01 sec 3.90 GBytes 33.6 Gbits/sec [ 5] 7.01-8.00 sec 3.94 GBytes 33.9 Gbits/sec [ 5] 8.00-9.00 sec 3.83 GBytes 32.9 Gbits/sec [ 5] 9.00-10.00 sec 3.87 GBytes 33.3 Gbits/sec - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate [ 5] 0.00-10.00 sec 38.1 GBytes 32.7 Gbits/sec sender [ 5] 0.00-10.01 sec 38.1 GBytes 32.7 Gbits/sec receiver iperf Done. The following entries appear in the kernel logs on Linux guest: [ 157.294081] enp3s0: bad gso: type: 1, size: 8960 [ 157.294298] enp3s0: bad gso: type: 1, size: 8960 [ 157.623938] enp3s0: bad gso: type: 1, size: 8960 [ 157.938094] enp3s0: bad gso: type: 1, size: 8960 [ 158.249957] enp3s0: bad gso: type: 1, size: 8960 [ 158.593349] enp3s0: bad gso: type: 1, size: 8960 [ 158.909346] enp3s0: bad gso: type: 1, size: 8960 [ 159.236646] enp3s0: bad gso: type: 1, size: 8960 [ 159.236721] enp3s0: bad gso: type: 1, size: 8960 [ 159.236745] enp3s0: bad gso: type: 1, size: 8960 This is also reproduced for bare metal Windows 11 PC with bridged physical network adapter to br0 on kvm host. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
