Hub 3 / Compal CH7465-LG (TG2492LG) and CGNV4 Latency Cause

[Datalink]

Good Day Ladies and Gentlemen,

Greetings from the other side of the pond, so to speak.  Over the last few weeks I've been perusing various user forums across North America and Europe for issues related to Intel Puma 6 modem latency.  Of those forums, your Hub 3 stands out as yet another Puma 6 based modem where users see continuous latency no matter what site is used or what online game is played. Considering all of the problems that are on the go, the following information should be of interest to all Hub 3, Compal CH7465-LG and Hitron CGNV4 modem users.  There is much more to post regarding this, so this is a start, to alert VM users as to the real cause of the latency and hopefully engage the VM engineering staff, via the forum staff, with Arris.  I am surprised to see that there has been no mention on this board of users from other ISPs who are suffering the exact same issues with their modems, so, this may come as a surprise to some, and possibly old news to others.

So, the short story ........

The Hub 3 / Compal CH7465-LG (TG2492LG) & Hiton CGNV4 modems are Intel Puma 6 / 6 Media Gateway (MG) based modems.  These modems exhibit high latency to the modem and high latency thru the modem.  The latency affects all IPV4 and IPV6 protocols, so it will be seen on every internet application and game.  The basic cause is the processing of the data packets thru a CPU software based process instead of thru the hardware processor / accelerator.  It appears that a higher priority task runs periodically, causing the packet processing to halt, and then resume.  This is observed as latency in applications and in ping tests to the modem and beyond.  For the last several weeks, Hitron, along with Intel and Rogers Communications in Canada have been addressing the latency issue within the Hitron CGNxxx series modems.  To date, only the IPV4 ICMP latency has been resolved.  Although this is only one protocol, it does show that a Puma 6MG modem is capable of using the hardware processor / accelerator with good results.  Currently Rogers is waiting for further firmware updates from Hitron which should include an expanded list of resolved protocol latency issues.  For Arris modems, "Netdog" an Arris engineer indicated last week that Arris was onboard to address the issue for the Arris SB6190 modem.  That should be considered as good news for any Arris modem (read Hub 3) user as Arris should be able to port those changes over to other Puma 6/6MG modems fairly quickly.  This is not a trivial exercise and will probably take several weeks to accomplish.  Note that there is no guarantee at this point that it is possible to shift all packet processing to the hardware processor / accelerator without suffering from any packet loss side effects.  Time will tell if all of the technical issues can be resolved with the current hardware included in the Puma 6/6MG chipset.  Last night, Netdog loaded beta firmware on selected test modems on the Comcast Communications network.  As this was only done last night, it's too soon to tell what this version resolves and if it was successful or not.  Netdog has contacts with staff at Comcast, Rogers, Charter and Cox Communications to fan out beta versions and modifications for testing.  I'd say its time to add Virgin Media and/or Liberty Global to that group as well.

Recent activity:

Approx three weeks ago a DSLReports user, xymox1 started a thread where he reported high latency to an Arris SB6190 and illustrated that with numerous MultiPing plots.  This is the same latency that I and other users with Rogers communications have been dealing with for months so it came as no surprise.  As well as reporting via that thread, xymox1 took it upon himself to email several staff members at Arris, Intel, Cablelabs and others.  The result of that campaign was Netdog's announcement, last week, that Arris was fully engaged at resolving the issue.  That has led to last nights release of beta firmware, although as I indicated its too early to determine what the beta firmware resolves, if anything.

The original thread that xymox1 started is here:

https://www.dslreports.com/forum/r31079834-ALL-SB6190-is-a-terrible-modem-Intel-Puma-6-MaxLinear-mis...

Yesterday, DSLReports issued a news story covering the thread:

https://www.dslreports.com/shownews/The-Arris-SB6190-Modem-Puma-6-Chipset-Have-Some-Major-Issues-138...

Today, Arris responded:

https://www.dslreports.com/shownews/Arris-Tells-us-Its-Working-With-Intel-on-SB6190-Puma6-Problems-1...

That response was also picked by Multichannel.com

http://www.multichannel.com/news/distribution/intel-arris-working-firmware-fix-sb6190-modem/409379

This is more news likely to appear in the next few days as additional tech and news staff pick up on this issue.

Hub 3 observations:

Like many others using a Puma 6/6MG modem, Hub 3 users are experiencing latency when they ping the modem, or ping a target outside of the home, game online or use low latency applications.  The common misconception is that this is Buffer Bloat. It's not. Its most likely a case of the packet processing stopping while the CPU processes a higher priority task.  The packet processing is done via the CPU no matter what mode the modem is operating in, modem mode or router mode and no matter what IPV4 or IPV6 protocol is used.  Normally, the latency is just that, latency.  The exception are UDP packets. In this case there is latency and packet loss.  The result of that is delayed and failed DNS lookups, and poor game performance for games that use UDP for player/server comms or player/player comms.

Can this be fixed?

So far, it appears that the answer is yes.  Rogers Communications issued beta firmware to a small group of test modems in October.  This version shifted the IPV4 ICMP processing from the CPU to the hardware processor / accelerator, resulting in greatly improved performance in ping latency.  At the present time we are waiting for the next version firmware which should shift other protocols over to the hardware processor / accelerator.  That can be seen in the following post:

http://communityforums.rogers.com/t5/forums/forumtopicpage/board-id/Getting_connected/message-id/369...

The details and results of last nights beta release to the Comcast group have yet to be seen.

At this point there is enough reading to keep most staff and users busy.  My intention is to post some of the history leading up to this point and instructions on how to detect the latency and packet loss.  This is not thru the use of a BQM.  I had hoped to post this all at once but events are moving much faster than I had thought they would.  For now this should suffice to get the ball rolling.

Below is a link to a post with a couple of HrPing plots from my 32 channel modem to the connected CMTS.  This shows the latency that is observed and reflects what others have posted in this forum using Pingplotter and HrPing.

https://www.dslreports.com/forum/r31106550-

HrPing is one of the freebie applications that can be used to monitor the latency to and thru the modem. 

Pingplots with Pingplotter which show the latency from my modem to the CMTS can be found in the first two to three rows of my online image library at Rogers Communications, located below.  They are essentially what the BQM would look like if you were able to zoom into the plot to the point where you could see the individual ping spikes.  Those ping spikes are common to Puma 6 and Puma 6MG modems.

http://communityforums.rogers.com/t5/media/gallerypage/user-id/829158

 [MOD EDIT: Subject heading changed to assist community]

[mobculture]

I think it was new. The engineer told me that they had just received new stock of SH2 on Tuesday, but didn't know why!

I should add that I tried buying one from eBay a couple of months ago and adding that, but they told me I couldn't do it. Luckily, I got a refund!

[Guybrush85]

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@mobculture wrote:
I think it was new. The engineer told me that they had just received new stock of SH2 on Tuesday, but didn't know why!

I should add that I tried buying one from eBay a couple of months ago and adding that, but they told me I couldn't do it. Luckily, I got a refund!

---

Yeah, that's what I thought, although I'm sure it will be a 2ac?

Anyway, back to the original thought, don't buy one 2nd hand as they can't activate it. 

[RidingTheFlow]

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@mobculture wrote:
I think it was new. The engineer told me that they had just received new stock of SH2 on Tuesday, but didn't know why!

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Well, so somebody is lying, obviously. Either ones who claim there is no new SH2 and there never will be, or ones who claim otherwise 😉

Maybe they've recently decided to actually buy some SH2 to give to people who complain, who knows. As usual, total informational blackout and clueless staff does not improve the situation.

[Drewley]

I wonder if they had a new batch of SH2ACs made..

[Guybrush85]

I don't think it's lying per say and I don't think they had a new batch made up. It's probably just low amounts of stock and not like stockpiled up in the usual places so took someone high up the chain to get it into the correct hands.

What I can say is the person I spoke to I know well so if he's saying he can't activate a used modem, then he can't. 

[RidingTheFlow]

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@Guybrush85 wrote:

What I can say is the person I spoke to I know well so if he's saying he can't activate a used modem, then he can't. 

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Well, I also spoke to person who know well (just a week ago), I was assured that there will never be a new SH2, and haven't been for ages - "manufacturing contract long ended".

That they speak coherently and/or hold high position does not mean they are telling the truth or have correct information (but for people of high position I'd say second is unlikely).

I also was told for some very qualified people that it will be impossible to activate a new SH2 if it was just lying in storage for very long time.

By "can't activate a used modem" they always mean "not allowed to". Not *technically impossible* - yes, its impossible for *some* staff, but there is staff who can just override the system, if ordered to.

[Guybrush85]

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@RidingTheFlow wrote:

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@Guybrush85 wrote:

What I can say is the person I spoke to I know well so if he's saying he can't activate a used modem, then he can't. 

---

Well, I also spoke to person who know well (just a week ago), I was assured that there will never be a new SH2, and haven't been for ages - "manufacturing contract long ended".

That they speak coherently and/or hold high position does not mean they are telling the truth or have correct information (but for people of high position I'd say second is unlikely).

I also was told for some very qualified people that it will be impossible to activate a new SH2 if it was just lying in storage for very long time.

By "can't activate a used modem" they always mean "not allowed to". Not *technically impossible* - yes, its impossible for *some* staff, but there is staff who can just override the system, if ordered to.

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And I'm not debating that, I'm saying that someone in the job that would do this kind of thing day in and day out, who is what the system will send out, can't do it, both from it not allowing him from a system level and being told the company line on it.

So unless you have some way of getting to person X that 'may' have the power to do this, then you're stuffed. As of yet, nobody has managed to get a used modem re-added that I've seen, so there's no point in postulating about it. 

The only thing we can say is that a few people have managed to get hold of a new modem and get it added. How they got it and how they got it added is not something we're likely to find out.

[RidingTheFlow]

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@Guybrush85 wrote:

So unless you have some way of getting to person X that 'may' have the power to do this, then you're stuffed.

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This pretty much summarises the whole situation, regardless of how you are trying to get SH2 🙂

[astrohominis]

To me, it seems quite likely that the distribution of people upgrading to SH3's that don't care about this latency issues, is greater than those that do.

If we accept this premise, then it seems there ought to be a surplus of now unused used SH2's existing out there in the wild. (eBay evidence would seem to support this hypothesis)

If that's the case, then a possibly cheap solution would be to

1) Start up a refurbishment program to incentivize users to send the old SH2's back to VM. (possibly even with a small reward eg £10 credit)

2) Send these refurbished SH2's to customers that actively complain.

3) Focus on ensuring SH4 is fast tracked for production and tested to be latency-bug free to prevent a re-occurrence.

Of course, given that it's likely a sensible solution (in my not so humble opinion), it's also almost guaranteed not to happen 😛

[JJC1138]

I got my price increase letter today and cancelled my account. In short: it was 25 minutes on the phone, and cancellations haven't been told about the SH3 issue, but here's the details of what happened in case anyone is interested:

Letter came in the post (not email). Big Virgin Media logo and "Your monthly bill is changing" on the front so it's hard to miss.

It says my bill is going up £2.99 per month from 1st November (I'm on VIVID Gamer 200). The letter has a whole spiel about how great they are, including "You're with the gaming champions" 🙄 and at the bottom says "We hope you want to carry on enjoying all this with us. But if not, don't worry — you can change or cancel your package at any time before 30th September 2017 without paying any cancellation charges. Just visit virginmedia.com/discovergamer for more information."

As you can see, that page has more spiel ("You’ve got game-changing broadband" — that one's certainly true), and an 0800 phone number to call to cancel.

That seems to just connect to the normal customer services phone system so you have a few menu options to go through, and you're asked to enter the numbers corresponding to three letters from your phone password (I had to scramble to find that).

Then "we're busier than usual so there might be a wait of up to ten minutes", pop hold music (yes, yes, you are beautiful and powerful Robbie Williams) for 10 minutes and then a person asks how they can help you.

I said I want to cancel because of the price rise. He asked if there was anything he could help with. I said no, I'm unhappy with the service so definitely want to cancel. He says he'll put me through to cancellations. 30 seconds on hold and he comes back to say they're busy so there'll be a wait of around 10 minutes and do I want to wait. I say yes.

10 minute wait, same hold music playlist

Guy answered; asks how he can help. I say I'm unhappy with the service and I'd like to use the price rise to cancel my contract. He asks why I'm unhappy. I brace myself and say "have you heard about the latency problem with the Super Hub 3 that causes problems with gaming?" and he says no, and he's actually a PC gamer and doesn't have any problems with latency and asks for more details (I wonder if the system was smart enough to put me through to someone who knows about gaming because I'm on the gamer service, or if that was just luck?). So I told him that there's a latency spike of a couple hundred milliseconds every 2 seconds. He says he gets good pings on Counter-Strike and he's on a Super Hub 3. I try and give a bit more detail about how it can be hard to notice because your average ping can still be good despite the spikes, and tell him there's a long forum thread about it. He was still a bit dismissive about it (no ill will towards him, he's just doing his job trying to keep the account) and suggested I talk to tech support, but he put through my cancellation.

The cancellation date is 10th September so exactly 30 days from now. Apparently my next bill payment will go out as usual and then two days after cancellation I'll get a final bill with a pro-rated refund for the part of my next payment that isn't used.

So that's that. I signed up with another ISP online while I was on hold.

Sorry this post is so long, but if I can just say one more thing: The guy on the phone mentioned that he hasn't played Counter-Strike for a bit because it's stressful because of cheaters and incompetent players. And that made me think that I bet there are millions of gaming VM customers who don't know about this latency issue, because it's so odd and easy to miss with normal performance measurements, but who are just finding that online gaming isn't as fun as it used to be, and attributing it to cheaters or that they're not as good as they used to be or whatever. And that's really sad, I think.