13.0-STABLE FreeBSD 13.0-STABLE #0 stable/13-4a4a17495 virtualbox-ose-6.1.22 I have noticed that using bridged networking with any of the emulated adapters that network performance is poor. I particularly notice when trying to scp files to a Linux guests (RHEL 8.3, Alma 8.4), Solaris 9. I found that networking is normal if I select virtio network on the guest. I have switched physical network cards, and the problem persists.
Try to disable HW offloads on NIC: ifconfig igb0 -rxcsum -txcsum -vlanhwtso -lro -tso4 -tso6 down up
That made a world of difference. The nic works normally. Thank you!
(In reply to Ivan Rozhuk from comment #1) Thanks! helped for me also. Env (if this gives someone any clue): Host: FreeBSD 12.4-RELEASE r372781 GENERIC amd64 on (very old) Intel S3210SH platform with Xeon X3210 CPU @2.13 and em0 <Intel(R) 82566DM-2 ICH9 AMT> Virtualbox: virtualbox-ose-6.1.36 (from packages) virtualbox-ose-kmod-6.1.36 (built from ports for 12.4) Guests: Win 2003 Server (32-bit) using virtio-net driver Win XP using emulated PCNet-FAST III adapter Ubuntu 14.04/i686 using emulated Intel PRO/1000MT adapter All three has poor performance - ~5KB/s by wget under Ubuntu from local server, failure to transfer files with "resource disappeared" error under Windows - including W2K3 with virtio. "ifconfig em0 -rxcsum -txcsum" was sufficient to restore normal network speed.