Would you be open to sharing your virtio-9p setup details and performance numbers?In my measurements virtio-9p is about twice as fast as NFS but unlike NFS it doesn't cache. So once things are cached NFS is much faster.
Then in the freebsd guest /etc/fstab has entries like this:-s 8,virtio-9p,src=/usr/src \
-s 9,virtio-9p,obj=/usr/obj \
As for performance, see this -hackers post: https://lists.freebsd.org/archives/freebsd-hackers/2026-May/006363.htmlsrc /usr/src p9fs rw 0 0
obj /usr/obj p9fs rw 0 0