Re: bhyve VM not getting as much upload bandwidth as the host

Hi all,

> Am 14.08.2023 um 11:30 schrieb Miroslav Lachman <000.fbsd@quip.cz>:
> 
> On 14/08/2023 10:49, Odhiambo Washington wrote:
>> I had the following in sysctl.conf:
>> net.link.tap.up_on_open=1
>> net.link.bridge.pfil_member=0
>> net.link.bridge.pfil_bridge=0
>> net.link.bridge.pfil_local_phys=1
>> So I only did:
>> sysctl -w net.link.bridge.pfil_onlyip=0
>> sysctl -w net.link.bridge.pfil_local_phys=0
>> Nothing has changed for the linux VM.
>> Windows11 VM is getting download/upload speed of 40Mbps/37Mbps while a Debian12 VM is getting download/upload of 37Mbps/45Kbps.
>> Maybe there is an issue with the Linux itself?
> 
> I never had this solved. Even my FreeBSD guest on FreeBSD host with VirtualBox is slow as few hunderds kB/s
> It was like 10Mbps with Bhyve. I only use VMs for testing but installing packages is always so slow. So you are not alone. I would really like to know how to improve the network speed with virtualized environment.

This looks weird to me. I run lots of VMs in production on TrueNAS CORE
- essentially FreeBSD 13-STABLE with bhyve and all of them get near gigabit
speed with bridged networking.

Guests:

Windows
Ubuntu
FreeBSD (OPNsense)

Specifically the OPNsense VM can route 700-800 Mbit/s across gigabit interfaces.

All my VMs use VirtIO network drivers - do yours?

Odhiambo, another minor thing:

> ifconfig_em1="inet w.x.y.z netmask 255.255.255.0 mtu 1492 -tso -lro -txcsum -rxcsum"

A bridge member interface must not have a layer 3 address. You must put the IP address
on the bridge interface itself and only configure

ifconfig_em1="mtu 1492 -tso -lro -txcsum -rxcsum up"

But this is most probably not connected to your performance problem. It just breaks
other things if you have an IP address on a bridge member ;-)

Why are you lowering the MTU of em1? Does that carry over to the bridge interface?
What's the MTU of the emulated interface in your Linux VM?

Kind regards,
Patrick
-- 
punkt.de GmbH
Patrick M. Hausen
.infrastructure

Sophienstr. 187
76185 Karlsruhe

Tel. +49 721 9109500

https://infrastructure.punkt.de
info@punkt.de

AG Mannheim 108285
Geschäftsführer: Daniel Lienert, Fabian Stein