Re: Lagg and multi-gigabit questions/proablems

> On Nov 9, 2022, at 14:32, Patrick M. Hausen <hausen@punkt.de> wrote:
> 
>> Am 08.11.2022 um 06:38 schrieb Chris Ross <cross+freebsd@distal.com>:
>> I have a newer Freebsd 12.3 system with lagg across two 1gbe interfaces.  There are a collection of vlan interfaces on the lagg.
>> 
>> I would _expect_ to be able to get 2gbps, or just shy thereof.
> 
> You are aware that LAGG/LACP will give you only a single interface's bandwidth
> for a single stream? That's by design, because reordering of TCP packets is bad.
> 
> You would need to test with multiple endpoints, because most commonly distribution
> is per IP address hash.

Ahh, thank you.  While that makes perfect sense and I may have known it at
some point, I didn’t realize that now.  I was of course testing with only the 
one stream.

Just now, I ran two iperf3 streams at the same time, from the same hosts.
For control, from my Mac with Gbe to the server, which got ~950 Mbits/s
in a single stream, got a consistent ~430 on each of two streams.
From the FreeBSD system with 2Gbe LAGG, my results were not as
consistent, but above 1Gbit/s.  Sometimes it will run at 950 Mbits/s
and 700 Mbits/s in parallel, but other times it will run at variable speeds
more like 600-700 each.  In all cases, I think the total was
1200 Mbits/s or more.

I’m curious why I was seeing some stream at consistent high speeds,
and others at varying lower speeds, but I’ll just write that off as load
or activity on the hosts.

Thanks all.  Sorry for the noise, hopefully this being in the archives
will help someone else.  :-)

                   - Chris