On Mon 21 Dec 2015 02:14:20 AM you wrote:
> Hi Thomas,
> 
> [...]
> 
> > When I'm part of any kind of p2p "swarm", I can't upload reliably. It's so
> > bad that I've rarely ever seen more than 20KBps per peer, and it's
> > usually between 0 and 10KBps (5KBps is pretty average :o).
> > 
> > I did some testing this weekend, and tried out the latest stable pfSense
> > on it (I was running Debian Sid), and things improved a bit. Now I'm
> > using an RT- AC66U
> 
> [....]
> 
> First of all, your network setup if not entirely clear. Is your p2p
> client running on your Soekris net6501?

Sorry for not including the important details.

My network setup was like so:

Cable Modem -> 6501-50 -> Netgear smart switch -> lan + wifi 

> If so, is that wifi network with the Asus RT-AC66U between the Soekris
> and the upstream network?

Nope.

> If not, why do you think the Soekris hardware is responsible for the
> poor network performance?

Remembering back, some of the problems may have appeared around the same time. 
And I've always had issues with the soekeris, especially with linux. Back when 
i got it, the linux support was /poor/ at best, and the bios/hardware was 
almost worse. Who releases a product with out checking its not running at 
optimal performance, and doesn't check the thermal profiles?

> My first two suspects of bad network performance would be:
> 
> 1. Poor wifi. What is the packet loss and jitter (variation in latency)
> between the wifi client and wifi AP? Ideally, this should be about 1 ms
> RTT without much fluctuations, but 3 or 5 ms is usually acceptable too.
> If you see latency over 10 ms, or over 5% packet loss, that is most
> likely the culprit. Look into the location of the wifi, the channels
> used by you and neighbours, etc. If you haven't done so, download a wifi
> scanner to find out which channels are in use, and how strong they are.
> Note that for 2.4 GHz (802.11g, 802.11n), an AP in e.g. channel 5 may
> still interfere with channels 3 thru 7. 5 GHz (802.11n, 802.11ac) has
> less users, but is more susceptible to interference by walls, floors and
> doors.

Wifi is reasonable. I'm picky about that. But the problems occur over wired 
GbE as well.

> 2. Network saturation because of the use of UDP-based p2p traffic. TCP
> has a fairly commanding congestion control algorithm, which
> significantly backs-off in case of congestion. A fair portion of p2p
> clients uses UDP, which lacks congestion control, and may continue to
> send traffic. Unfortunately, this often results in higher latency,
> collisions, and ultimately collapse of performance. It certainly pays of
> to configure your p2p client to only use at max 50-75% of your upstream
> bandwidth capacity.

I had my shorewall install QoS things. Did not help. My p2p use has fallen off 
quite a lot lately. And my upstream to p2p has suffered a LARGE hit. It's 
nearly impossible to share back.

> Other sources might be poor TCP congestion control tuning, buffer bloat
> or the opposite (too small buffers), poor Ethernet flow control, poor
> upstream network. Insufficient TCP-offloading in your NIC, or -more
> generally- not powerful enough CPU in your Soekris 6501 would be at the
> bottom of list of suspects.

I'm not worried about the CPU performance in the soekeris. It should be more 
than enough. CPU use was generally very low. I'm suspecting a 
hardware/firmware issue.

> Hope this works.
> 
> Freek

-- 
Thomas Fjellstrom
[email protected]
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