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]

[jesstes]

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@chriscdotcodot wrote:
Any idea how you convince them that you need the beta firmware?

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Apparently; marking the words of a manager at virgin media second line support "post in our community, we have many people working on it, they can help you to become a trialist".

Basically you just need to wish very hard and then post a request anywhere in the community board (like we don't know that in more than one year nobody from virgin had the guts to write anything meaningful about the matter). Good luck to you and all of us! They are not even fixing the problem on businesses hubs, also based on intel's puma soc, and in a business scenario having a line with high latency is matter of money earned or lost (VPN, conference calls, VOIP, servers, real-time sensitive tasks, etc).

I find out from the mentioned manager that they are tied up with a contract to Arris, hence you are not allowed to play your games or have decent latency until they reach their quota with them. This manager also told me "i know we have a hub 4 in production that will come out in 2018". Let's hope for a broadcom chipset, or at list for something non intel.

screenshot taken from http://www.virginmedia.com/shop/broadband/compare.html

Why major media (I mean TV) don't covert this story? Surely a public demonstration of such magnitude would force virgin do something asap just for sake of their allegedly good reputation.

The truth is that the problem will be solved, but not because of virgin or us, but just because Arris' main market is the US, a land where you get sued easily, where public opinion moves revenue with no mercy, where cable ISPs distribute their own modes/routers but still let you use any compatible device available in the market. The Americans will fix it for us with the magic of the market rules.

Why are we not allowed to have the options to use modems from a third party with virgin? is there any technical reason? and why nobody fights for it? 

[audleyvm]

Here is a SH2 to SH3 replacement (yesterday) which clearly shows the latency between the two hubs.

[BrokenFibre]

Well, I've waited long enough.  Now that my NOWTV connection has been running a month I decided to call virgin and cancel my TV package and reduce my BB down to Vivid50 on a rolling 30 day (as a backup connection)........they can't do that.  If I cancel my TV and want to drop my broadband it will start a new 12 month contract, which I don't want.

As such I asked to cancel the lot and they did.  No offers nothing, just a yes it will cease on the 15th Jan.  Seems they don't care that much about retaining customers.

[q3dm6]

I've recently rejoined Virgin and I'm likely to terminate my contract over this issue (Still in my 14 day cool off period). This thread was started over a year ago and there's still no fix or workaround. I have absolutely zero confidence reading through this thread this issue will ever be resolved, nor do Virgin care.

[tommey]

Was hoping for an early Xmas present from Virgin but looks like we won't even get a response from them in this thread let alone a wider trial of the Beta firmware. not that it actually fixes anything but at least it makes the BQM look better..... right Virgin?

[Luke_113]

Has anyone been in touch with any of the tech or generic news outlets or started a twitter campaign or dare I say even raised it to their local MP? (Recently I mean, in this climate news outlets love a good complaint story to get behind) This along with other issues such as peering seem to be really turning off a lot of customers from Virgin Media or Virgin Media Business, and with G.Fast and FTTP only around the corner Virgin’s refusal to do anything about this and actually sort the problem could be their undoing.

[LdGallifryan]

I have tried getting News involved.

No reply or anything.. might be up Virgin's Backside..

Provided live graph's, this Thread.. the lawsuit page, Reddit Page, my experiences, my permission to use my name in the story.. just nothing to pull the plug on these Rats!.

I was going to get my MP involved but, I don't think they can do much..
There is another route with the OfCom regulator.. but that is a shot in the dark, as you need to get a "Letter of Deadlock" from Virgin Media.. and for me it is hard to get as they refuse to admit there is a Issue.. so no issue to sort out according to them, over the phone and the engineers.

I wish HyperOptic was in my area but, am considering switch to Highest Tier on BT Infinity...
As I am unhappy with my services for the past 2 and a half years!

[Luke_113]

I also wish hyperoptic or gigaclear were in my area unfortunately they have a ‘gentlemen’s agreement’ with BT that they detailed to me that essentially means they’ll never lay fibre down my hill - as I approached them via their website, called and emailed to have a proper conversation, so....I can get Virgins fastest product, but I’ll not get that stably and can’t Game in the evenings at the moment, due to the issue addressed in this thread and also the issue with their peering into the EU post 4pm (so 5pm on the continent) being abysmal at the moment. So I either get rock solid low latency from VDSL via BT et al, OR I get 200mb download and latency that goes up and down like the wind blows.

Why can’t Virgin see that if they properly address a couple of problems their customer base wouldn’t be so prone to erupting into a raging mob? It’s their lack of openness about what they’re actually doing, as you read all the time on these forums of people speaking to this person and that person and the resolution times being wildly different. I can’t believe that Virgin is that much of a black box to work at?!

[LdGallifryan]

There is one extreme idea I have been thinking about..

That we all have a March to there headquarters in the UK and do demonstrations and offer the news to come as well and expose VM for being Lazy and Pathetic.

(But that is the most extreme thing I can think of) part from switching the Ghost Gaming Broadband or BT..

[Andrew-G]

"I have tried getting News involved."

I think that the issue is too complicated for them to explain, and the consequences insufficiently dramatic.  The unwashed masses think that (claimed) bandwidth is speed, and that a big Mbps number equals a fast connection.  Gamers know what lag is, and that's near enough latency, but even then, who (a) reads news, (b) knows what "lag" or latency are, and (c) gives a tinker's cuss?  Explaining what latency is, and what the impact is far too difficult (the journalists could do it, but they know readers will switch off and go to read an article with gruesome picture, pretty girl pic, or celebrity scandal.  Journalists also need stories that enable the use of shrill, outraged headlines DUSTED with capitals TO emphasise into the title.  Take this from the Daily Mail: "They're kit fu fighting! Angry cat BODY SLAMS rival as the pair come to paws".  Now imagine: "Virginmedia issue crap cable modem RIDDEN with flaws: Angry gamers miss shots!  Corporate suits suffer JERKY videocalls!"

Having said that, I'm a member of the Consumer's Association - I'll see if they can be interested, although I doubt it given their generally geriatric customer base.