Line #3 upstream had a bit of a minor struggle with sustaining a 6 dB target SNRM in the past. The SNRM did not droop much at all, and indeed was rigidly fixed at 6dB precisely throughout the day when the strange jump occurred, but there had always been a fair few ES regularly, so the noise background must I suspect have been a bit spiky. There was no interleave upstream on line #3 which I think was really bad and probably was part of the answer to why it wasn’t coping perfectly. In contrast line #1 upstream had an interleave depth of 8 and no problems.
So is that all there is to it: the line suddenly improved massively, but how?
Here are the full raw stats from a later time still, well after the jump; Line #3, 2023-01-26 13:35 :
xdslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason: 8000
Last initialization procedure status: 0
Max: Upstream rate = 854 Kbps, Downstream rate = 3172 Kbps
Bearer: 0, Upstream rate = 728 Kbps, Downstream rate = 3151 Kbps
Link Power State: L0
Mode: ADSL2 Annex A
TPS-TC: ATM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 2.9 9.6
Attn(dB): 63.0 40.1
Pwr(dBm): 18.4 12.4
ADSL2 framing
Bearer 0
MSGc: 59 11
B: 98 22
M: 1 1
T: 1 4
R: 0 0
S: 0.9950 1.0000
L: 796 184
D: 1 1
Counters
Bearer 0
SF: 15627005 61809
SFErr: 1138 2578
RS: 0 1518713
RSCorr: 0 0
RSUnCorr: 0 0
Bearer 0
HEC: 1928 1079
OCD: 14 0
LCD: 14 0
Total Cells: 1878187096 433810943
Data Cells: 315389796 39977601
Drop Cells: 0
Bit Errors: 74335 108019
ES: 23322 25322
SES: 2029 3
UAS: 647465 645747
AS: 252710
Bearer 0
INP: 0.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 16.16 17.00
OR: 32.16 8.00
AgR: 3171.61 733.13
Bitswap: 49374/49380 3374/3374
Total time = 152 days 22 hours 26 min 44 sec
FEC: 568397 43732
CRC: 117611 31648
ES: 23322 25322
SES: 2029 3
UAS: 647465 645747
LOS: 268 0
LOF: 618 0
LOM: 205 0
Latest 15 minutes time = 11 min 44 sec
FEC: 0 0
CRC: 2 8
ES: 2 4
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 0 0
CRC: 8 0
ES: 7 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 22 hours 26 min 44 sec
FEC: 0 0
CRC: 328 355
ES: 298 323
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 1 day time = 24 hours 0 sec
FEC: 0 0
CRC: 393 820
ES: 348 795
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Since Link time = 2 days 22 hours 11 min 49 sec
FEC: 0 0
CRC: 1138 2578
ES: 1025 2016
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
NTR: mipsCntAtNtr=0 ncoCntAtNtr=0