diizzyy:

Speedtest is a very bad way of measuring performance, does iperf show anything strange between your clients?

Spider-Vice:

LAN to LAN is normal. Any WAN to LAN activity on a 100 Mbps link is affected. Not just SpeedTest. Any download, any interaction.

bjonglez:

Can you perform an "offline" test? Basically, you plug one computer to the WAN port, another computer with a "100 Mbps cable" to a LAN port, and perform bidirectional iperf between the two.

It should rule out any strangeness from your ISP (bursts, etc)

Spider-Vice:

I didn't run iperf but I did test the link copying between two computers connected by the LAN (via Windows' file sharing) and I get the correct 100 Mbps speed (as the cable I use for this device can only do 100 Mbps). As I said, I tested this, and it only happens in connections that originate in the WAN:

i.e.
Downloading from the Internet with a 100 Mbps cable: Strange behaviour
Downloading from the Internet with a Gigabit cable: OK, full 95 Mbps Internet speed.
Copying files to the LAN with a 100 Mbps cable: OK
Copying files to the LAN with a Gigabit cable: OK

Stock firmware does all those OK.

Will be back with an iperf output though if really needed.

Brother-Lal:

Seems to work for me, with a utp 2 pair cable:

http://paste.debian.net/hidden/c6e7a2ec/

run on: LEDE Reboot 17.01.0 r3205-59508e3
with NAT enabled, local net was 192.168.2

might it be that the cable has some issues beyond the 100mbps link?
Or the other router has some problem with the cable?

Spider-Vice:

I didn't iperf, but I attempted a file copy between two local clients and this works normally. My issue is restricted to WAN to/from LAN connections. The issue is not present in the stock firmware, it's not a cable issue.

Brother-Lal:

I measured the performance between WAN and LAN, yes.

which lede version did you flash, and do you have any details about your configuration?

Spider-Vice:

Were you using a Gigabit cable? Because it works normally with one, it only starts bugging out with a 100 Mbps one.

I still had this issue in the first LEDE Reboot version (I think one of the RC's). I have been tracking the git for quite some time and didn't see anything relevant about this for the router's SoC. I will test the latest version soon.

rotanid:

What is a Gigabit Cable and what is not? There is no such thing.
Maybe your cable is broken? What's the cables specification? Cat.5e is the required minimum for 1000Base-T Ethernet.

Spider-Vice:

Let me be clearer then:

With a Cat5 cable, I get this issue on LEDE doing LAN to/from WAN.
With a Cat5e cable I do not.
On the stock firmware I have no issues with both reaching my maximum WAN speed.

Edit: Tested on latest LEDE. Issue still present.
Cat5: LAN to LAN OK, 98-99 Mbps. WAN to/from LAN NOT OK. Capped at 20-30 Mbps.
Cat5e: LAN to LAN OK. WAN to/from LAN OK. 95 Mbps which is my Internet speed.
Stock Firmware: Both cable types OK, same max speed.

It feels like whenever a Cat5 cable is connected, the router falls back to Half-Duplex for some reason.

Brother-Lal:

Yes, i used a Cat5 2 pair and a Cat5 4 pair cable cable for these tests.
And performance was nominal at the 100/1000Mbps levels where it should be.
So either its a speciality of the cable, or of your router(s)

Did you connect the 2 pair cable at the client<->lan or router<->wan side?