VDSL Performance & Tuning

Forums › New Zealand Broadband › VDSL Performance & Tuning

1 | ... | 108 | 109 | 110 | 111 | 112 | 113 | 114 | 115 | 116 | 117 | 118 | ... | 285

40 posts

Geek
+1 received by user: 6

#845564 26-Jun-2013 13:11

I can't help with stats prior to profile upgrades, but I do have stats gathered at 5 minute intervals for the hours leading up to a drop from DLM-1 (latency changed from Fast to 8ms) and subsequent promotion at a forced resync a few hours later back to DLM-1 in the 10 days following a port change. If anyone is interested I can plot any of CRC per minute/last 15, FEC per minute/last 15, US and DS attainable and actual, also spectrum analysis for the period leading up to the downward DLM change. Or I could collate the raw data into CSV format.

Software Engineer: Java, C++, SS7 and IP networking

HiTM4N

256 posts

Ultimate Geek
+1 received by user: 22

Trusted

#845566 26-Jun-2013 13:18

Looking at my SNR...I'm at 4db currently! (no tweaks in place)

Love of all phones, computers and gadgets

SamF

1598 posts

Uber Geek
+1 received by user: 252

Trusted

#845645 26-Jun-2013 15:43

That's due to your poor line, your SNR margin is being eroded by line issues.

HiTM4N

256 posts

Ultimate Geek
+1 received by user: 22

Trusted

#845658 26-Jun-2013 16:24

SamF: That's due to your poor line, your SNR margin is being eroded by line issues.

Small success story for you guys

Just disconnected 4 out of 5 jacks, leaving only a single jack connected.
Previously there was a splitter right after the etp, that split to two jacks, one in dinning room one in master bedroom. Master bedroom then was in series with 3 other jacks.
I disconnected the master bedroom at the first splitter.
The results are below.

BEFORE:

AFTER:

I'm still going to install a master filter and replace all the old wiring with new CAT6 at some stage, but this is a great improvement i think!
Just shows how much difference your internal wiring makes!

Love of all phones, computers and gadgets

sidefx

3775 posts

Uber Geek
+1 received by user: 1295

Trusted

#845664 26-Jun-2013 16:43

@HiTM4N: That is a nice increase! Must have been an odd splitter though, or faulty, if disconnecting the non-DSL side caused that sort of increase :) Or maybe a non-VDSL splitter?

"I was born not knowing and have had only a little time to change that here and there." | Octopus Energy | Sharesies
- Richard Feynman

HiTM4N

256 posts

Ultimate Geek
+1 received by user: 22

Trusted

#845676 26-Jun-2013 16:58

sidefx: @HiTM4N: That is a nice increase! Must have been an odd splitter though, or faulty, if disconnecting the non-DSL side caused that sort of increase :) Or maybe a non-VDSL splitter?

well when i say spilter...

Love of all phones, computers and gadgets

Quic Broadband

Move to New Zealand's best fibre broadband service (affiliate link). Free setup code: R587125ERQ6VE. Note that to use Quic Broadband you must be comfortable with configuring your own router.

hio77

'That VDSL Cat'
13036 posts

Uber Geek
+1 received by user: 3896

ID Verified

Trusted

Lizard Networks

Subscriber

#845683 26-Jun-2013 17:08

what an improvement! looks like i missed quite a lot while on holiday however.. looking forward to hopefully finding a nice surprise with DLM on my line when i get home tomorrow!

defiantly get CAT6 ran and split/direct line.. should get a bit more of a jump after that.

looks like you have cleaned up almost all the RFI on your line too!

#include <std_disclaimer>

Any comments made are personal opinion and do not reflect directly on the position my current or past employers may have.

sidefx

3775 posts

Uber Geek
+1 received by user: 1295

Trusted

#845684 26-Jun-2013 17:11

HiTM4N:
well when i say spilter...

lol, ok that explains it then! That's not a master filter so you just had a big mess of multiple daisy chained jacks and un terminated stubs all connected to your VDSL line. No wonder you had issues :P A master splitter looks like a small block solid box, with 1 pair going in and 2 pairs coming out. I'd still say with that wiring either get a proper master filter, or a decent cable straight from incoming pair to modem with nothing else connected in any other way. That's the best way to get the most out of VDSL. Thoguh 28/10 is still nice! :) Just the errors that are a bit of a worry.

BTW: is that how it's wired right now? Or was that before disconnecting the master bedroom etc?

"I was born not knowing and have had only a little time to change that here and there." | Octopus Energy | Sharesies
- Richard Feynman

HiTM4N

256 posts

Ultimate Geek
+1 received by user: 22

Trusted

#845689 26-Jun-2013 17:21

That's before.
All I did was cut off the connection to the master bedroom.
I plan to pull all that out and install a master filter and proper cabling

Love of all phones, computers and gadgets

SamF

1598 posts

Uber Geek
+1 received by user: 252

Trusted

#845700 26-Jun-2013 17:59

@stevehodge: What did you use to generate those SNRM graphs?

I also found your last pre-17a post. Looks like your stats went like this (All on DLM-1):

Date Profile Sync     CRC SNRM SNRM Tweak
26/1   8b        45000    0.5 14 +2
27/1   8b        50600    40   11   +2
2/2    17a       58600    0.33    14   +2
5/2    17a   61624    0.28    12      0

So prior to the pre-17a 'testing' period you had a fairly low CRCPM rate, a fairly high sync rate which would have been higher, at least 47mbit, if you weren't using a +2 SNRM tweak, but not higher than 50mbit.

Thinking about my 3db drop today, I don't think it was due to any kind of line issue per-say as my sync rate increased by ~2mbit. Just prior to my 3dB drop I was running a -4dB tweak, syncing at 54mbit with a <2 CRCPM error rate. I seem to recall this happening to me at an earlier stage as well.

stevehodge

393 posts

Ultimate Geek
+1 received by user: 52

#845815 26-Jun-2013 23:02

SamF: @stevehodge: What did you use to generate those SNRM graphs?

The data is being captured by my linux server using Collectd which is a general data gathering framework that I was already using to log the server's disk temperatures. I wrote a simple module for it in perl (thanks to the stuff hio77 figured out) to grab what I wanted from the Fritz - sync rate, errors, SNRM, and temp. Then there is a webserver running "cgp" (Collectd Graph Panel) that displays the data.

I also found your last pre-17a post. Looks like your stats went like this (All on DLM-1):

Date Profile Sync     CRC SNRM SNRM Tweak
26/1   8b        45000    0.5 14 +2
27/1   8b        50600    40   11   +2
2/2    17a       58600    0.33    14   +2
5/2    17a   61624    0.28    12      0

So prior to the pre-17a 'testing' period you had a fairly low CRCPM rate, a fairly high sync rate which would have been higher, at least 47mbit, if you weren't using a +2 SNRM tweak, but not higher than 50mbit.

Yeah my error rate was ok on that sync. I had other syncs with worse error rates though (e.g. 3 per min). And I've got a screenshot here from Dec 4 that has SNRM of 5 and 6 CRC/min. Back then we though we needed very low error rates to stay on DLM-1 which was why I had the +2 tweak on.
Definitely never saw 50 Mbit except for that one just prior to 17a.

Thinking about my 3db drop today, I don't think it was due to any kind of line issue per-say as my sync rate increased by ~2mbit. Just prior to my 3dB drop I was running a -4dB tweak, syncing at 54mbit with a <2 CRCPM error rate. I seem to recall this happening to me at an earlier stage as well.

Yeah I don't think it's a line issue either. I think it's the DSLAM doing something.

Dyson

Shop now for Dyson appliances (affiliate link).

SamF

1598 posts

Uber Geek
+1 received by user: 252

Trusted

#845829 26-Jun-2013 23:46

So the only thing we can really conclude from the evidence we have is that DLM-1, low (<0.5) error rates and maybe a lower sync speed threshold of 45mbit may count as factors in 17a selection.

That also makes sense in my case (assuming my -3dB SNRM change today was a 17a 'test'). My recent history was basically:

Sync   CRC SNRM SNRM Tweak
55000 8 8   -4.5
36000 0     22    +10
49500 0.1   12    0
54500 <2    8    -4
56500 10    5       -4
49500 0.2 12    0

All on DLM-1

JonoNZ

274 posts

Ultimate Geek
+1 received by user: 43

#845874 27-Jun-2013 08:39

Another resync this morning, looks like another DLM change, DLM-2 now? Sync speed slightly up too: speedtests over wifi now frequently over 44Mbps down.

Bearers generic info DS US
Payload rate [Kbps]: 47828 10350
Attenuation [dB]: 11.0 23.0
Margins [dB]: 12.5 18.4
Output power [dBm]: 13.5 -4.0

Number of bearers: 1
Bearer 0 DS US
INP [DMT symbols]: 0.00 0.50
Delay [ms]: 8.00 8.00
Depth []: 193 0.00
R: 6 0

EDIT: for clarity.

stevehodge

393 posts

Ultimate Geek
+1 received by user: 52

#846012 27-Jun-2013 11:22

JonoNZ: Another resync this morning, looks like another DLM change, DLM-2 now

Yes, looks like DLM-2. You'll probably get put on DLM-1 on Saturday morning.

hio77

'That VDSL Cat'
13036 posts

Uber Geek
+1 received by user: 3896

ID Verified

Trusted

Lizard Networks

Subscriber

#846287 27-Jun-2013 16:20

soo, DLM was nice to me.. moved down to DLM2 yet again this morning.. think i might need to give the modem its 5 mins to cool the CRCs hopefully.. they are a tad high for my liking (3CRCPM currently)

#include <std_disclaimer>

Any comments made are personal opinion and do not reflect directly on the position my current or past employers may have.

1 | ... | 108 | 109 | 110 | 111 | 112 | 113 | 114 | 115 | 116 | 117 | 118 | ... | 285