Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[siofjofj]

Thanks for the update, if you are happy with your connection now, and it stays that way, then that is a good result.

However, the DLM has applied interleaving to your connection (you can see this from the interleave depth 'D' for bearer 0 downstream being a value other than 1, in this case 8) despite the fact you have G.INP enabled, pointing to it having detected some instability. I'm not 100% sure what the process the DLM should follow after a DLM reset on a good line now, perhaps someone else can advise, but I believe on Huawei cabinets nowadays you start with G.INP and no interleave and then, subject to no problems, gradually step down in SNRM to 3 dB. I would assume that the reduced SNRM of 4.5 dB is not this however since you have interleave, and is instead the result of the resync taking place at a relatively electrically quiet time, it will probably go back up to 6 dB with a corresponding speed decrease if you resync now.

As to why this has happened, you only have had 22 errored seconds (ES) over the 5.5 days before your last resync which is nowhere near enough to upset the DLM (you can read about the thresholds here https://kitz.co.uk/adsl/DLM.htm). You do however have 22 SES, which may result in a DLM response (no idea what the thresholds are for SES). Have you had any resyncs other than the last one? Did you have DSLstats collecting data over the past week? If so, you may be able to see a burst of errors at some point in time.

Edit: Sorry, complete rubbish. See below.

[jimmyca69]

Thanks for the update, if you are happy with your connection now, and it stays that way, then that is a good result.

However, the DLM has applied interleaving to your connection (you can see this from the interleave depth 'D' for bearer 0 downstream being a value other than 1, in this case 8) despite the fact you have G.INP enabled, pointing to it having detected some instability. I'm not 100% sure what the process the DLM should follow after a DLM reset on a good line now, perhaps someone else can advise, but I believe on Huawei cabinets nowadays you start with G.INP and no interleave and then, subject to no problems, gradually step down in SNRM to 3 dB. I would assume that the reduced SNRM of 4.5 dB is not this however since you have interleave, and is instead the result of the resync taking place at a relatively electrically quiet time, it will probably go back up to 6 dB with a corresponding speed decrease if you resync now.

As to why this has happened, you only have had 22 errored seconds (ES) over the 5.5 days before your last resync which is nowhere near enough to upset the DLM (you can read about the thresholds here https://kitz.co.uk/adsl/DLM.htm). You do however have 22 SES, which may result in a DLM response (no idea what the thresholds are for SES). Have you had any resyncs other than the last one? Did you have DSLstats collecting data over the past week? If so, you may be able to see a burst of errors at some point in time.

Thanks for the info, haven't experienced any drops during the day over the past week so it seems ok. I have set DSL stats to run over the next 24hrs to capture more info. I had noticed a huge increase in FEC errors (as can be seen in stats).

It actually did it again last night with SNR dropping and connection speed increasing again...

Code: [Select]

xdslctl info --stats
xdslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason:    1
Last initialization procedure status:   0
Max:    Upstream rate = 23056 Kbps, Downstream rate = 76002 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 75425 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Link Power State:       L0
Mode:                   VDSL2 Annex B
VDSL2 Profile:          Profile 17a
TPS-TC:                 PTM Mode(0x0)
Trellis:                U:ON /D:ON
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):        3.3             7.5
Attn(dB):        17.7            0.0
Pwr(dBm):        12.4            7.3

                        VDSL2 framing
                        Bearer 0
MSGc:           -6              26
B:              243             237
M:              1               1
T:              0               42
R:              10              16
S:              0.0000          0.3781
L:              19726           5374
D:              8               1
I:              254             127
N:              254             254
Q:              8               0
V:              0               0
RxQueue:                84              0
TxQueue:                21              0
G.INP Framing:          18              0
G.INP lookback:         21              0
RRC bits:               0               24
                        Bearer 1
MSGc:           154             -6
B:              0               0
M:              2               0
T:              2               0
R:              16              0
S:              6.4000          0.0000
L:              40              0
D:              3               0
I:              32              0
N:              32              0
Q:              0               0
V:              0               0
RxQueue:                0               0
TxQueue:                0               0
G.INP Framing:          0               0
G.INP lookback:         0               0
RRC bits:               0               0

                        Counters
                        Bearer 0
OHF:            0               3833994
OHFErr:         1               12
RS:             1237128848              3418545
RSCorr:         25741074                54
RSUnCorr:       0               0
                        Bearer 1
OHF:            1991283         0
OHFErr:         0               0
RS:             19912218                0
RSCorr:         210             0
RSUnCorr:       0               0

                        Retransmit Counters
rtx_tx:         481602125               0
rtx_c:          2300909         0
rtx_uc:         125781          0

                        G.INP Counters
LEFTRS:         77              0
minEFTR:        73985           0
errFreeBits:    2146507717              0

                        Bearer 0
HEC:            0               0
OCD:            0               0
LCD:            0               0
Total Cells:    295860731               0
Data Cells:     235025356               0
Drop Cells:     0
Bit Errors:     0               0

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

ES:             33              215
SES:            32              0
UAS:            150             118
AS:             31994

                        Bearer 0
INP:            51.00           0.00
INPRein:        1.00            0.00
delay:          0               0
PER:            0.00            3.98
OR:             0.01            64.22
AgR:            75502.61        20063.54

                        Bearer 1
INP:            4.50            0.00
INPRein:        4.50            0.00
delay:          3               0
PER:            16.06           0.01
OR:             79.68           0.01
AgR:            79.68   0.01

Bitswap:        5148/5148               17/17

Total time = 7 days 22 hours 26 min 59 sec
FEC:            100479778               1753
CRC:            1698            249
ES:             33              215
SES:            32              0
UAS:            150             118
LOS:            3               0
LOF:            22              0
LOM:            0               0
Latest 15 minutes time = 11 min 59 sec
FEC:            647483          0
CRC:            0               0
ES:             0               0
SES:            0               0
UAS:            0               0
LOS:            0               0
LOF:            0               0
LOM:            0               0
Previous 15 minutes time = 15 min 0 sec
FEC:            861850          0
CRC:            0               0
ES:             0               0
SES:            0               0
UAS:            0               0
LOS:            0               0
LOF:            0               0
LOM:            0               0
Latest 1 day time = 22 hours 26 min 59 sec
FEC:            40692343                183
CRC:            551             29
ES:             11              22
SES:            10              0
UAS:            38              28
LOS:            1               0
LOF:            7               0
LOM:            0               0
Previous 1 day time = 24 hours 0 sec
FEC:            24948171                189
CRC:            0               23
ES:             0               20
SES:            0               0
UAS:            0               0
LOS:            0               0
LOF:            0               0
LOM:            0               0
Since Link time = 8 hours 53 min 13 sec
FEC:            25741074                54
CRC:            1               12
ES:             1               9
SES:            0               0
UAS:            0               0
LOS:            0               0
LOF:            0               0
LOM:            0               0
NTR: mipsCntAtNtr=0 ncoCntAtNtr=0
 >
I will keep DSLstats running now until tomorrow for further analysis. Is there specific info to pull out of DSLstats to check?

[siofjofj]

Interesting. The SNRM does seem to have dropped to 3 dB now (ignore what I said about the 4.5 dB earlier, evidently this was the 4 dB step in the gradual reduction from 6 dB to 3 dB), as it should do on a stable line. I didn't know this still happens if interleaving has been applied. Perhaps interleaving will be removed later?

Just keep an eye out for any bursts of CRCs.

[mrk26]

Looking on stats there is no interleaving, 3ms delay is standard for G.inp?

[siofjofj]

I think you're looking at bearer 1 there. Bearer 0 has D = 8 on the downstream which is interleave depth 8 right?

Edit: Bearer 0 also has delay = 0 on the downstream, perhaps that does indeed mean no interleave? Not sure I understand that, on my G.INP enabled connection I have D = 1 and delay = 0. How can there be an interleave depth of 8 but no delay? Is this perhaps ReTx high? I think someone a bit more familiar with VDSL needs to comment. In any case, the delay is what you really care about, so if it really is zero then that is good news.

[j0hn]

I think you're looking at bearer 1 there. Bearer 0 has D = 8 on the downstream which is interleave depth 8 right?

Edit: Bearer 0 also has delay = 0 on the downstream, perhaps that does indeed mean no interleave? Not sure I understand that, on my G.INP enabled connection I have D = 1 and delay = 0. How can there be an interleave depth of 8 but no delay? Is this perhaps ReTx high? I think someone a bit more familiar with VDSL needs to comment. In any case, the delay is what you really care about, so if it really is zero then that is good news.

That's G.INP.

The interleaving depth (D) would be over 1,000 on such a high sync if it was traditional low interleaving.
INP would be 3 - 3.5
delay would be above 0 (minimum of 8ms delay on OpenReach).
That's all on Bearer 0

Bearer 1 being shown at all tells us G.INP is active.

There's no G.INP framing, no Bearer 1 and no rtx figures if G.INP is off.
There would be no mention of G.INP at all if it wasn't enabled.

[siofjofj]

Thanks j0hn, that clears that up. Sorry for the confusion jimmyca69, looks like all is well with your connection!