Interleaving Killing Pings (DLM Lockout Request)

[Enverex]

So the backstory is I have a problematic line. The problem isn't so much the line itself, but that DLM always thinks there are problems, but there really aren't.

It's stable and works well, unfortunately over time DLM will keep lowering and lowering the speed and turning interleaving up to silly levels but this isn't needed at all. I have no idea what causes DLM to think there are issues because I don't get drop-outs or any other issues of that sort.

Now back on ADSL2+ it was all good and well because I simply asked TalkTalk to lock the line to 6dB Fastpath which gave me the max speed the line would achive whilst getting rid of that pesky interleaving which was making my life a nightmare in online games.

I've had a second line fitted nearly a few days ago now, although it's not a new line, it's off the same run of cable (as BT now apparently run all lines to houses as 2 or 4 cores, so the engineer simply used the second, still available core in the cable). Everything was great for the first day or so. 10ms pings to game servers, fantastic.

Now everything is back to its old tricks, Interleaving is showing on the modem and my pings are back to around 26ms or so.

Now I had a feeling this may happen so I asked the engineer about locking the line profile so DLM can't interfere again. Now I've seen BT reps on the forum say "It can't be changed" on the forum, so I posed this to the engineer as well and he said that's outright not true. Even on Fibre the OpenReach engineers can contact the engineers within BT (not the front-line customer service people) and get profile changes/locks like this actioned to negate line issues like this.

Below is the raw output from the HG612...

Status: Showtime
Retrain Reason: 1
Last initialization procedure status:   0
Max:    Upstream rate = 5480 Kbps, Downstream rate = 29536 Kbps
Bearer: 0, Upstream rate = 5506 Kbps, Downstream rate = 25974 Kbps

Link Power State:       L0
Mode:                   VDSL2 Annex B
VDSL2 Profile:          Profile 17a
TPS-TC:                 PTM Mode(0x0)
Trellis:                UN /DN
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):        6.1             6.1
Attn(dB):        25.2            0.0
Pwr(dBm):        12.3            6.5
                        VDSL2 framing
                        Bearer 0
MSGc:           22              26
B:              51              159
M:              1               1
T:              64              40
R:              12              12
S:              0.0637          0.9216
L:              8040            1493
D:              509             1
I:              64              86
N:              64              172
                        Counters
                        Bearer 0
OHF:            130511          57846
OHFErr:         4               2
RS:             33348790                2313437
RSCorr:         97094           1
RSUnCorr:       8               0

                        Bearer 0
HEC:            1               0
OCD:            1               0
LCD:            1               0
Total Cells:    26648949                0
Data Cells:     128419          0
Drop Cells:     0
Bit Errors:     0               0

ES:             35127           358
SES:            416             0
UAS:            84              74
AS:             534

                        Bearer 0
INP:            3.00            0.00
INPRein:        0.00            0.00
delay:          8               0
PER:            4.09            9.25
OR:             54.74           27.66
AgR:            26028.32        5533.73

Bitswap:        280/280         2/2

So yeah, as you can see speeds are fine (as far as this line is concerned due to the line length and possible other factors) and it's nice and stable, but I need to get interleaving turned off and the profile locked in place otherwise it's simply going to get worse (it had trained down to ~19Mb on the old line before and was still slowly dropping over time with interleaving still on). It becomes a never-ending degredation until DLM is turned off and the profile is locked.

DLM simply cannot be allowed to run on this line otherwise it will just get worse due to misdiagnosis.

[ray_dorset]

As far as I know, DLM runs on all lines and there is no way to get it locked or turned off.

[Enverex]

The OpenReach engineer stated that this was a lie. I had heard it was impossible to remove which in iteself makes no sense which is why I presented him with the question in the first place.

I mentioned this in the original post.

[ray_dorset]

Maybe he was confusing it with the DLM on ADSL, which can be altered by BT.

[Enverex]

Then I'm back in the same boat as before. An internet connection that will forever get worse with **bleep** pings because magically no-one seems to have control over their own systems. Not only does that sound stupid, it sounds like a lazy excuse to not have to try and deal with problems.

"Oh, it's all just done by a system, there's nothing we can do about it". No-one in their right mind would design a system that cannot be overridden, especially as it was already in place when ADSL2+ existed.

[Valthos]

this is not true.

engineer can request 4 profiles 1 of which is custom.

he can select interleaving on and off and upload and download aswell as several other settings with IMP etc.

im on a custom profile that i got changed to by the engineer.

interleaving caused me issues aswell.

its been forced off on upload and download at the expense of a slightly lower sync rate.

i dropped to 77mb sync 20 upload so i lost about 3mb.

my pings are 8ms to BBC.co.uk

and 5ms to google.com

C:\WINDOWS\System32>ping google.com

Pinging google.com [31.55.163.251] with 32 bytes of data:
Reply from 31.55.163.251: bytes=32 time=5ms TTL=56
Reply from 31.55.163.251: bytes=32 time=5ms TTL=56
Reply from 31.55.163.251: bytes=32 time=4ms TTL=56
Reply from 31.55.163.251: bytes=32 time=5ms TTL=56

Ping statistics for 31.55.163.251:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 4ms, Maximum = 5ms, Average = 4ms

C:\WINDOWS\System32>

[ray_dorset]

So why didn't the engineer do this?

[Valthos]

i guess i got lucky with a engineer that knew what he was doing. 

he showed me from his laptop he had dirrect access to all the settings in the cab.

i even begged him to up the transmit power from the cab on my line. but he could not at the moment as there was still lots of ADSl in the area and it causing issues for them.

he said once the cab is full the line power is raise to help combat crosstalk.

[Enverex]

He didn't do it because he was literally just fitting the new line, we didn't know if it was going to be an ongoing issue with this new line or not.

[ray_dorset]

With any luck, Openreach will give ISPs the ability to set custom DLM profiles soon - hopefully before you have any problems