40% Network Bandwidth loss on Raspi 3B

Dear All,

I’m running IPFire on a Raspberry PI 3B since almost 6 years now! I’m running IPFire 2.27 (aarch64) - Core-Update 180.

Lately, I noticed that from my 100Mbit/s Internet Connection, only about 40-50MBit/s reach my computer. Since a lot of things can influence that (Routers, Switches, WiFi, the ISP ripping me off, etc…) I started to investigate a little to figure out the bottleneck.

Using iPerf3 I tested:

  1. WAN-Bandwidth: Connection from Internet (iPerf3 Server speedtest.studiofunk.de) → Cable Modem → to a MacOS Laptop: 110Mbits/s (with that I know the ISP is not ripping me off).
  2. LAN-Bandwidth: Connection from the Raspi running IPFire → a router → a 5GHz WiFi-AP → to my MacOS computer: 95MBits/s (tested both transmission directions, with that I know the 100Mbit-LAN is working properly).
  3. Bandwidth to Raspi: Connection from Internet (iPerf3 Server ** speedtest.studiofunk.de**) → Cable Modem → to Raspi running IPFire: 60-70MBit/s (iPerf3 running on Raspi’s Console).
  4. System Bandwidth through all components (Internet to my computer): 40-50MBit/s.

Seems like my Raspi running IPFire is the bottleneck. Funny thing, some months back, I would easily achieve a System Bandwidth of 80-85Mbits/s with the same setup.

Additional information: IPS is enabled, but disabling it does not make a noticeable difference. QoS is disabled.

Any ideas what the reason might be? Perhaps it is time to upgrade the HW… Thanks!

SOLVED: Meanwhile, I did an additional experiment which improved the situation. I was using the built-in Ethernet Port in my Raspi for WAN connection (100Mbit). I changed that to an external Gigabit to USB adapter and these are my new results for my tested scenarios:

Scenario 3: Bandwidth to Raspi from the Internet increased from approx. 65Mbits/s to 80Mbits/s.
Scenario 4: System Bandwidth increased from approx. 45Mbits/s to 75Mbits/s.

With that I’m back to where it was before, and I can live with that change. Still wondering why this changed, since I did not make any changes on the wiring nor HW…

I’ve experimented and used RPi3Bs and RPi4Bs for a few years and 50 MBits is pretty “normal”.

They were built for one network connection and not built for two. They just don’t have the “power” to do it all.

A RPi4B will help. BUT keep in mind there are many versions of the RPi4B and some of the newer versions are harder to make work. (I’ve only tested and used revision 1.1)

The above is from:

Also, the RPi5 is not tested. I think they are just being released in small quantities.

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