RE: Slow 'real world' network performance

[Marcin Gondek <drixter%e-utp.net@localhost>]

Hi Peter,

I've using my below settings:
https://fido.e-utp.net/2025/01/22/NETBSD-SYSCTL.html

Some of them you already used, I've compiled it from many places, they help me to speed-up NetBSD.

Thanks,

--
Marcin Gondek / Drixter
http://fido.e-utp.net/
AS56662

-----Original Message-----
From: netbsd-users-owner%NetBSD.org@localhost <netbsd-users-owner%NetBSD.org@localhost> On Behalf Of Peter Miller
Sent: Friday, October 24, 2025 8:41 PM
To: NetBSD Users <netbsd-users%netbsd.org@localhost>
Subject: Slow 'real world' network performance

When I test my VPS server (virtualized server) with iperf3 or speedtest-cli, I get 700 Mbit/s. (it varies of course depending on network congestion) If I run a test server like this

python3.12 -m http.server -b $my_ip

and then download 100MB and 1000MB test files, I only get 80 Mbit/s. I have seen as bad as 4 Mbit/s, when seconds later I can test 400 Mbit/s on iperf3.

These aren't one off results. I have 3 virtual servers with different hosts and locations, and the performance gap is similar on all of them. With Linux, FreeBSD and OpenBSD I get download speeds inline with iperf3 test results.

Last night I did my python server test on the same server, downloading the 1000 MB file to my FreeBSD laptop and got:
NetBSD 160 Mbit/s
FreeBSD 640 Mbit/s
OpenBSD 528 Mbit/s (it got to 640 Mbit/s but averaged 528) I didn't test Linux (Debian) last night, but it's usually similar to FreeBSD

Does anyone have suggestions on where to look next or some settings that might help. I have tried the TCP settings suggested here https://wiki.netbsd.org/tutorials/tuning_netbsd_for_performance/
but this post looks out of date, and it didn't increase performance.

--
Thanks
Peter