Change net qdisc and tcp congestion control defaults

I see that the current queue discipline is set to pfifo_fast, whilst tcp congestion control is set to cubic

sysctl net | grep -E "(qdisc|congestion)"

net.core.default_qdisc = pfifo_fast
net.ipv4.tcp_congestion_control = cubic

qdisc could be set to fq_codel and tcp congestion-control to bbr?

May be, same settings should to be set on the edge, the worker (host), and not just the guest (app) but I am not familiar with virt_io to know if there are more knobs to tune.