Menu
Reply
FatherFlump
  • 3
  • 0
  • 0
Joining in
306 Views
Message 1 of 4
Flag for a moderator

Another bad latency / ping time spike problem

Another case of intermittent bad ping times, this one in Beckenham.

I'm hoping experts can suggest what additional information I can capture so it's actionable by Virgin media folks. I have my cable modem in "modem" mode, and unfortunately my router (Google Wifi) doesn't allow me to enable ICMP responses, so I can't enable BQM without a bit of fiddling. That's probably my next step if this doesn't work.

Talking to call centre folks last week, I was (unsurprisingly) told that there were issues in my area due to over capacity, but this has been going on for months so I think may be in the last leg to my property and unrelated.

Ping times are generally not brilliant, but it's the spikes that are the killer. It might be the nature of the work I tend to do in the afternoon (remote access via chrome remote desktop, lost packets/latency leads to lots of repeated keypresses due to delays between key-down and key-up!), but it does seem worse in the afternoons. My son is also regularly impacted when playing games in the evenings.

Traceroute points to it being a problem outside of my local equipment, and I see the spikes when I connect my laptop directly to the back of the modem which seems to confirm that. All cables on my end are finger tight.

This is fairly typical, but lost packets and ping times over 250ms are common at the worst of times: (ping to www.google.com). I tend to see long times in the second and third hops. The 2- to 3- hop at the moment goes to either 80.1.225.185 or 80.1.225.65

 

 

Reply from 216.58.210.196: bytes=32 time=13ms TTL=55
Reply from 216.58.210.196: bytes=32 time=12ms TTL=55
Reply from 216.58.210.196: bytes=32 time=13ms TTL=55
Reply from 216.58.210.196: bytes=32 time=22ms TTL=55
Reply from 216.58.210.196: bytes=32 time=38ms TTL=55
Reply from 216.58.210.196: bytes=32 time=106ms TTL=55
Reply from 216.58.210.196: bytes=32 time=138ms TTL=55
Reply from 216.58.210.196: bytes=32 time=15ms TTL=55
Reply from 216.58.210.196: bytes=32 time=181ms TTL=55
Reply from 216.58.210.196: bytes=32 time=22ms TTL=55
Reply from 216.58.210.196: bytes=32 time=35ms TTL=55
Reply from 216.58.210.196: bytes=32 time=43ms TTL=55
Reply from 216.58.210.196: bytes=32 time=31ms TTL=55

Tracing route to www.google.com [216.58.204.228]
over a maximum of 3 hops:

  1     2 ms     2 ms     2 ms  192.168.86.1
  2    51 ms    19 ms    23 ms  10.117.124.1
  3    20 ms   119 ms    39 ms  80.1.225.185

ping -t  80.1.225.65

Pinging 80.1.225.65 with 32 bytes of data:
Reply from 80.1.225.65: bytes=32 time=160ms TTL=62
Reply from 80.1.225.65: bytes=32 time=104ms TTL=62
Reply from 80.1.225.65: bytes=32 time=87ms TTL=62
Reply from 80.1.225.65: bytes=32 time=20ms TTL=62
Reply from 80.1.225.65: bytes=32 time=74ms TTL=62
Reply from 80.1.225.65: bytes=32 time=26ms TTL=62
Reply from 80.1.225.65: bytes=32 time=184ms TTL=62
Reply from 80.1.225.65: bytes=32 time=10ms TTL=62
Reply from 80.1.225.65: bytes=32 time=15ms TTL=62
Reply from 80.1.225.65: bytes=32 time=105ms TTL=62
Reply from 80.1.225.65: bytes=32 time=52ms TTL=62
Reply from 80.1.225.65: bytes=32 time=105ms TTL=62
Reply from 80.1.225.65: bytes=32 time=74ms TTL=62
Reply from 80.1.225.65: bytes=32 time=41ms TTL=62

 

 

I rebooted my modem yesterday afternoon (Friday) and this afternoon (Saturday) I have SNR / post RS errors on the downstream like this:

 

 

Channel	Frequency (Hz)	Power (dBmV)	SNR (dB)	Modulation	Channel ID
1	298750000	-3.9	36	256 qam	21
2	138750000	-5.2	35	256 qam	1
3	146750000	-5	34	256 qam	2
4	154750000	-5.2	34	256 qam	3
5	162750000	-5.2	33	256 qam	4
6	170750000	-5.4	33	256 qam	5
7	178750000	-5	33	256 qam	6
8	186750000	-5	33	256 qam	7
9	194750000	-5	34	256 qam	8
10	202750000	-5	34	256 qam	9
11	210750000	-5.2	31	256 qam	10
12	218750000	-5.4	32	256 qam	11
13	226750000	-5.4	31	256 qam	12
14	234750000	-5.2	34	256 qam	13
15	242750000	-5	35	256 qam	14
16	250750000	-4.5	36	256 qam	15
17	258750000	-4.2	36	256 qam	16
18	266750000	-4	36	256 qam	17
19	274750000	-4.2	36	256 qam	18
20	282750000	-4.2	36	256 qam	19
21	290750000	-4	37	256 qam	20
22	306750000	-3.5	37	256 qam	22
23	314750000	-3.2	37	256 qam	23
24	322750000	-3.2	37	256 qam	24

Channel	Locked Status	RxMER (dB)	Pre RS Errors	Post RS Errors
1	Locked	36.6	61	0
2	Locked	34.9	42221	344
3	Locked	34.9	12530	458
4	Locked	34.3	19354	169
5	Locked	33.8	136278	135
6	Locked	33.8	167264	73
7	Locked	33.9	290677	214
8	Locked	33.9	343454	18
9	Locked	34.4	111793	45
10	Locked	34.9	4606	46
11	Locked	31.9	6120995	98
12	Locked	31.9	8884804	41
13	Locked	31.4	24174745	323
14	Locked	34.9	43559	80
15	Locked	35.5	22033	65
16	Locked	36.3	1605	31
17	Locked	36.3	204	69
18	Locked	36.6	118	0
19	Locked	36.6	106	0
20	Locked	36.3	97	1
21	Locked	37.3	44	0
22	Locked	37.3	43	0
23	Locked	37.6	92	4
24	Locked	37.3	63	7

 

 

I don't know what else to look for.

Thanks in advance!

0 Kudos
Reply
Gexton
  • 34
  • 0
  • 1
Tuning in
284 Views
Message 2 of 4
Flag for a moderator

Re: Another bad latency / ping time spike problem

Where about in Beckenham are, Park Langley way by any chance?

Lots of us having the same issues. heres a link to my BQM and I would imagine yours is similar.

https://www.thinkbroadband.com/broadband/monitoring/quality/share/2015a892ce570775e6b1383de376549576... 

I have the same setup as you, modem mode and google Wifi. I took out the google WiFi at the start of last week to rule it out after having speed issues. 

after reporting it three times and an engineer visit yesterday (who confirmed there was nothing locally wrong) Apparently everyone being at home is causing contention issues, running at 98% capacity. 
Theres a fault reference number for the area of F006805698.

if you have the time to call the call center that could help. The more people report and issue the more likely it will get reprioritised. Currently is scheduled to be fixed on the 10th June!

Personally it’s making it almost impossible to WFH, which is causing issues at work.

there’s also a ”Nextdoor” chain running on this here... 

https://nextdoor.co.uk/post/17592193670752?init_source=copy_link_share 

doesnt help you much but you can see you’re not alone.

FatherFlump
  • 3
  • 0
  • 0
Joining in
263 Views
Message 3 of 4
Flag for a moderator

Re: Another bad latency / ping time spike problem

Thanks for the info, Gexton. Nice to know I'm not alone. I'll mention the fault code if I manage to get through on the phone.

I've spent several hours in queues over the last week. Understandably, Virgin Media announced they're closing some call centres this week, and yesterday I was cut off after 40 minutes without reaching first line support. So, I'm not holding out much hope for an improvement in the coming weeks, unless one of the helpful Virgin engineers on here wants to suggest something.

> Where about in Beckenham are, Park Langley way by any chance?

I'm not too far away: Bramerton Road. I wonder how much infrastructure we share.

The odd thing is, according to speed tests, the throughput is reasonable. I'm supposed to be on 200 Mbps and the Google Wifi speed check usually shows me at 215 DS / 19 US, presumably measured in the early hours). Yesterday afternoon the latency was spiking as usual, but I was still reading 116 DS / 15 US. I've always assumed that the ISPs may game the speed tests a little, maybe by tweaking the packet scheduling to known speed test destinations, but those kind of numbers would be more than adequate for what I do.

I've been assuming that I would see a significant degradation in both bandwidth and latency if the infra was saturated. I should have paid more attention in my networking classes. This felt like packets being dropped due to bad hardware. Maybe the traffic load is similarly spiky...?

BTW / FYI - In the end I switched to tethering via an Android phone over 4G Vodafone, which I'd expect to have substantially lower bandwidth, and had relative high ping times (~60-80ms) but it was consistent and never went above 100ms. I managed to have perfectly tolerable VCs and remote computer access for a few hours. I'm told that a regular SIM will get throttled when tethering, but data-only SIMs that come with 4G modems won't. Obviously, at this point a lot of networks have sold out of 4G modems. I need to do some research into my work plan to see if I'm they're to get a monster bill or if I'll get throttled. If this continues and I'm able to, I'll be switching to a mobile network for work when it gets bad.  

This is what I'm getting on a Saturday evening. Anything from 15 to 752ms! No way I could do anything even vaguely latency sensitive with that.

 

Reply from 216.58.210.196: bytes=32 time=61ms TTL=54
Reply from 216.58.210.196: bytes=32 time=154ms TTL=54
Reply from 216.58.210.196: bytes=32 time=21ms TTL=54
Reply from 216.58.210.196: bytes=32 time=15ms TTL=54
Reply from 216.58.210.196: bytes=32 time=19ms TTL=54
Reply from 216.58.210.196: bytes=32 time=227ms TTL=54
Reply from 216.58.210.196: bytes=32 time=25ms TTL=54
Reply from 216.58.210.196: bytes=32 time=25ms TTL=54
Reply from 216.58.210.196: bytes=32 time=248ms TTL=54
Reply from 216.58.210.196: bytes=32 time=752ms TTL=54
Reply from 216.58.210.196: bytes=32 time=368ms TTL=54
Reply from 216.58.210.196: bytes=32 time=30ms TTL=54
Reply from 216.58.210.196: bytes=32 time=29ms TTL=54

 

 

0 Kudos
Reply
FatherFlump
  • 3
  • 0
  • 0
Joining in
155 Views
Message 4 of 4
Flag for a moderator

Re: Another bad latency / ping time spike problem

Well, today showed just how much worse things could get. I'm guessing something in the Beckenham area went down: lost packets around 25%, ping times through the roof (most above 100ms).

Even my son's friends in a different part of town that are on virgin media and who haven't previously been affect were complaining today. It was pointless using my broadband for anything other than downloads - slow, but they get there in the end. Anything interactive was pointless.

I really hope this is fixed soon. 

0 Kudos
Reply