Slow speed via DS-Lite (Unitymedia/Vodafone)

Hi guys,

I'm getting very slow speed via ds-lite (using the ds-lite package).
My setup is:
ISP (Kabel BW/Unitymedia/Vodafone) -> Connectbox (CH7465LG) -> APU2E4 (OpenWrt).

When doing speedtest on or via OpenWrt using IPv6 I get the advertised download speeds (250 Mbps).
Using ds-lite I get 10 Mbps at best.

Anyone has an idea what might be the problem?
I also tested with other machines and OSs by setting up the tunnel manually but got similar results.

Speedtest results (via ds-lite using speedtest-netperf):

Starting speedtest for 60 seconds per transfer session.
Measure speed to flent-eu.bufferbloat.net (IPv4) while pinging gstatic.com.
Download and upload sessions are sequential, each with 5 simultaneous streams.
.............................................................
 Download:   9.08 Mbps
  Latency: [in msec, 60 pings, 0.00% packet loss]
      Min:  30.241
    10pct:  60.597
   Median: 113.439
      Avg: 126.554
    90pct: 204.242
      Max: 347.890
 CPU Load: [in % busy (avg +/- std dev) @ avg frequency, 53 samples]
     cpu0:   2.2 +/-  2.1  @  661 MHz
     cpu1:   3.8 +/-  2.2  @  649 MHz
     cpu2:   9.0 +/-  3.3  @  667 MHz
     cpu3:   6.4 +/-  2.5  @  664 MHz
 Overhead: [in % used of total CPU available]
  netperf:   2.1
................................................................
   Upload:   2.71 Mbps
  Latency: [in msec, 64 pings, 0.00% packet loss]
      Min:  60.108
    10pct: 173.906
   Median: 334.109
      Avg: 345.475
    90pct: 474.734
      Max: 589.657
 CPU Load: [in % busy (avg +/- std dev) @ avg frequency, 56 samples]
     cpu0:   1.4 +/-  2.6  @  640 MHz
     cpu1:   3.0 +/-  2.9  @  631 MHz
     cpu2:   2.4 +/-  2.9  @  634 MHz
     cpu3:   3.2 +/-  3.7  @  632 MHz
 Overhead: [in % used of total CPU available]
  netperf:   0.7

Wan interface config:

config interface 'wan'
        option ifname 'eth0'
        option proto 'dslite'
        option encaplimit 'ignore'
        option peeraddr '2a02:8070::4002'

Route table for IPv4:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         *               0.0.0.0         U     0      0        0 ds-wan
192.0.0.1       *               255.255.255.255 UH    0      0        0 ds-wan
192.168.0.0     *               255.255.255.0   U     0      0        0 eth2
192.168.1.0     *               255.255.255.0   U     0      0        0 br-lan

hi, i have the exact same problem with the following configuration:
ISP (Kabel BW/Unitymedia/Vodafone) -> technicolor tc4400 -> Linksys WRT3200ACM
Did you manage to solve it and how? any help is much appreciated.

Unfortunately no. I've tried with different devices and OSes and got the same result every time. I suspect it is some sort of limitation on the ISP side.