Re: bad http download speed

[mlelstv%serpens.de@localhost (Michael van Elst)]

z411%omaera.org@localhost (z411) writes:

>Apparently VirtIO impacts performance in all OSes with
>high-latency/congested networks, but NetBSD is affected much more
>significantly. With E1000, NetBSD's performance is solid, although maybe
>a bit more sensitive to congestion.


I found:

https://superuser.com/questions/1767148/qemu-slow-network-performance-with-virtio-net-driver

that describes a similar symptom but this time with Linux as host and guest.
Workaround then (3 years ago) was to configure napi_weight=1 on the guest
to make each interrupt handle only one packet.

We have parameters at sysctl hw.vioif0 for a similar purpose, but they
don't seem to have a significant effect in my setup. But then, the
performance (with NetBSD being host and guest) isn't that bad either.