Virgin Media Latency

[adhsmith]

Hi there,

I have recently moved from Sky FTTC 160/30 G. Fast product to VMs 660/45, bandwidth wise VM has been spot on.

Foolishly I guess I expected the higher bandwidth network to be the faster more responsive network with respect to latency.

For a time I had Sky and VM side by side and on VPN to my office in Germany I was seeing 38-40ms on Sky but with VM on my VPN to the office and in fact on any tests in general it is 10-15ms worse, whilst it is not the end of the world I can still work productively and gaming pings have been acceptable, I'm no pro, but I would like to confirm this is an expected byproduct of running VMs older infrastructure and not an actual issue with my VM install.

I'm running a Hub4 and have tried it in and out of modem mode, modem mode doesn't improve things to any noticeable degree.

Is there anything I should look at or is it just what it is?

[Adduxi]

I'll throw in a wildcard here.  As you seem tech savvy, you could try an additional 80mm cooling fan on the top of the Hub 4.

There are several posts here about the poor air flow of the Hub 4 and have added a supplemental fan to increase the air flow and improve the performance.

If you have a spare fan lying around it's maybe worth a punt?

[adhsmith]

@Andrew-G

I'll get some updated BQM charts, I need to switch it out of modem mode though as my router rejects the packets for BQM right now so it looks all red 😄

But current router stats are here

Router stats 

PDFs of each page in a Google Drive folder as I kept hitting a 20k text limit copying and pasting, note we did have an outage yesterday that would probably show in the logs so there were some reboots before I gave up and switched to my back up internet for a bit.

@ Adduxi

Doubt temps are an issue, router is in the open and in a sheltered place, I am sure its fine, if there is any source of interference my end it is more likely that it sits next to Wifi router and also wireless phone hub, so I might try a little re-org.

[Andrew-G]

Those Google docs aren't working for me.  Post the hub data here as text - split the data into one post for Downstream, one for upstream one for network log, and make sure you capture all the data - it scrolls down.  Ctrl-A on a keyboard is useful here!

When posting the network log you'll get a confusing error message, just click "post" again.

[adhsmith]

Seems pasting as plain text works, shame as tables are much neater

Router status
Status
Downstream
Upstream
Configuration
Networklog
Refresh data
3.0 Downstream channels
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 139000000 7.900002 40.946209 QAM256 1
2 147000000 7.300003 40.366287 QAM256 2
3 155000000 7.400002 40.946209 QAM256 3
4 163000000 6.900002 40.946209 QAM256 4
5 171000000 6.599998 40.366287 QAM256 5
6 179000000 6.400002 40.946209 QAM256 6
7 187000000 6.300003 40.946209 QAM256 7
8 195000000 6.000000 40.946209 QAM256 8
9 203000000 5.699997 40.946209 QAM256 9
10 211000000 5.500000 40.366287 QAM256 10
11 219000000 5.300003 40.366287 QAM256 11
12 227000000 5.199997 40.946209 QAM256 12
13 235000000 5.099998 40.946209 QAM256 13
14 243000000 5.400002 40.366287 QAM256 14
15 251000000 5.800003 40.366287 QAM256 15
16 259000000 6.500000 40.946209 QAM256 16
17 267000000 6.000000 40.366287 QAM256 17
18 275000000 5.400002 40.366287 QAM256 18
19 283000000 5.199997 40.366287 QAM256 19
20 291000000 5.300003 40.946209 QAM256 20
21 299000000 6.199997 40.366287 QAM256 21
22 307000000 6.500000 40.946209 QAM256 22
23 315000000 6.199997 40.946209 QAM256 23
24 323000000 5.699997 40.366287 QAM256 24
25 331000000 5.400002 40.946209 QAM256 25
26 339000000 5.599998 40.946209 QAM256 26
27 347000000 5.400002 40.366287 QAM256 27
28 355000000 4.599998 40.366287 QAM256 28
29 363000000 4.500000 40.366287 QAM256 29
30 371000000 4.699997 40.366287 QAM256 30
31 379000000 4.800003 40.946209 QAM256 31

3.0 Downstream channels
Channel Lock Status RxMER (dB) Pre RS Errors Post RS Errors
1 Locked 40.946209 0 0
2 Locked 40.366287 0 0
3 Locked 40.946209 0 0
4 Locked 40.946209 0 0
5 Locked 40.366287 0 0
6 Locked 40.946209 0 0
7 Locked 40.946209 0 0
8 Locked 40.946209 0 0
9 Locked 40.946209 0 0
10 Locked 40.366287 0 0
11 Locked 40.366287 0 0
12 Locked 40.946209 0 0
13 Locked 40.946209 0 0
14 Locked 40.366287 0 0
15 Locked 40.366287 0 0
16 Locked 40.946209 0 0
17 Locked 40.366287 0 0
18 Locked 40.366287 0 0
19 Locked 40.366287 0 0
20 Locked 40.946209 0 0
21 Locked 40.366287 0 0
22 Locked 40.946209 0 0
23 Locked 40.946209 0 0
24 Locked 40.366287 0 0
25 Locked 40.946209 0 0
26 Locked 40.946209 0 0
27 Locked 40.366287 0 0
28 Locked 40.366287 0 0
29 Locked 40.366287 0 0
30 Locked 40.366287 0 0
31 Locked 40.946209 0 0

3.1 Downstream channels
Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33 96 4K 1880 QAM4096 759

3.1 Downstream channels
Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)
33 Locked 40 -1.2 48048836 0

[adhsmith]

Router status
Status
Downstream
Upstream
Configuration
Networklog
Refresh data
3.0 Upstream channels
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 32600000 43.020599 5120 KSym/sec 64QAM 5
2 39400000 42.770599 5120 KSym/sec 64QAM 4
3 53700000 42.520599 5120 KSym/sec 64QAM 2
4 46200000 42.520599 5120 KSym/sec 64QAM 3

3.0 Upstream channels
Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
1 US_TYPE_STDMA 0 0 0 0
2 US_TYPE_STDMA 0 0 0 0
3 US_TYPE_STDMA 0 0 0 0
4 US_TYPE_STDMA 0 0 1 0

[adhsmith]

Router status
Status
Downstream
Upstream
Configuration
Networklog
Refresh data
General Configuration
Network access
true
Maximum Number of CPEs
1
Baseline Privacy
true
DOCSIS Mode
3.1
Config file
cmreg-vmdg640-bbt078+voc-b.cm

Primary Downstream Service Flow
SFID
31362
Max Traffic Rate
690000278
Max Traffic Burst
42600
Min Traffic Rate
0

Primary Upstream Service Flow
SFID
31361
Max Traffic Rate
44000278
Max Traffic Burst
42600
Min Traffic Rate
0
Max Concatenated Burst
42600
Scheduling Type
bestEffort

[adhsmith]

Network Log
Time Priority Description
Mon Jul 19 02:36:58 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:36:58 2021 5 Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:36:58 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:37:20 2021 6 CM-STATUS message sent. Event Type Code: 5; Chan ID: 12; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:37:27 2021 3 Ranging Request Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:37:27 2021 3 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:37:45 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:16 2021 3 Ranging Request Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:17 2021 3 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:21 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:44 2021 3 Ranging Request Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:44 2021 3 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:54 2021 3 Ranging Request Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:38:54 2021 3 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 02:40:00 2021 5 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 13:19:26 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 19 21:10:45 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:01:19 1970 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 20 01:09:50 2021 5 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 20 01:10:15 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Thu Jul 22 22:39:13 2021 4 DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Thu Jul 22 22:49:14 2021 6 CM-STATUS message sent. Event Type Code: 5; Chan ID: 12; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Thu Jul 22 23:52:47 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Fri Jul 23 05:52:47 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Fri Jul 23 21:09:51 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Sun Jul 25 02:55:31 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Sun Jul 25 03:15:14 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:01:19 1970 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 26 02:02:26 2021 5 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 26 02:02:51 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 26 22:23:59 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 03:33:31 2021 5 RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 05:52:15 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:25:40 2021 3 SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:25:41 2021 6 CM-STATUS message sent. Event Type Code: 2; Chan ID: 1; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:25:45 2021 5 Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:27:51 2021 3 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:35:07 2021 5 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:35:10 2021 5 RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:41:54 2021 6 CM-STATUS message sent. Event Type Code: 4; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:45:20 2021 3 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:46:46 2021 5 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:46:54 2021 5 RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 09:47:07 2021 6 CM-STATUS message sent. Event Type Code: 23; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 11:30:09 2021 3 SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 11:30:12 2021 5 Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 11:31:23 2021 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 27 11:31:29 2021 6 CM-STATUS message sent. Event Type Code: 5; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;

[Andrew-G]

Well, network log is full of timeouts and sync failures, which explain those spikes on the BQM.  The error counters on downstream are all zeroes, which unless you've just rebooted the hub is nonsense (I suspect another Hub 4 firmware bug).  Power levels are OK across the D3.0 downstream channels, but the range across both D3.0 and 3.1 channels may be a problem - I can't be certain because the info available on operating standards is sparse.

I'd wait for staff to pick this up and advise; But you really shouldn't be seeing those spikes.

[adhsmith]

Yup hub was rebooted yesterday when there was an outage in the area. I'll pop it back on router mode tonight when no one is using it and let it run for a few days.

[Tom_F]

Hi @adhsmith, thanks for getting in touch - apologies for the connection issues you've experienced.

I can confirm there's still a known area issue ongoing, it's currently estimated to be resolved by 03 AUG 2021 17:20. If you continue to experience problems with your connection please don't hesitate to get back to us so we can check for another update and take further action if required.

Tom