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]

[lynxblaine]

I have genuinely had a much better experience with the 608 firmware to before, DNS searches don't fall, websites load more evenly and gaming has been much improved. Someone did do a deep analysis of the new firmware and it is genuinely loads better. Not as good as BT but it never will be. 

[tricksterdude]

Can anyone tell me if these problems exist in modem mode or is it just when the superhub is in router mode? Is the 608 firmware fine in modem mode?

I'm considering upgrading, I already own a decent router, I never use virgin's hubs as a router, but don't want to take the leap until I know my gaming won't be affected.

[justasking1992]

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@tricksterdude wrote:

Can anyone tell me if these problems exist in modem mode or is it just when the superhub is in router mode? Is the 608 firmware fine in modem mode?

I'm considering upgrading, I already own a decent router, I never use virgin's hubs as a router, but don't want to take the leap until I know my gaming won't be affected.

---

I got a SH3 today because my SH1 had fully died, it was not receiving enough downstream no matter what even with Attuenators it would not recieve enough power levels and would disconnect often. 

I am running mine in router mode and everything is fine, obviously I am connected via Ethernet straight to my PC.

So far with my SH3 it is already on 603 firmware and I live in the Leeds 8 area and gaming feels the same, if anything Ping has dropped by 5~ on CSGO and League of legends. And I have been running ping tests since I first got it and have no issues with high ping spikes or packet loss really so far.

[justasking1992]

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@lynxblaine wrote:

I have genuinely had a much better experience with the 608 firmware to before, DNS searches don't fall, websites load more evenly and gaming has been much improved. Someone did do a deep analysis of the new firmware and it is genuinely loads better. Not as good as BT but it never will be. 

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With my experience so far for a day with the SH3 I can only agree with this, I had a SH1 until today that has sadly died. 

So far my SH3 with 608 firmware in Router mode and gaming feels no different than it did with my SH1, if anything I have lost 5~ ping on some of my games. No issues with packet loss or choke either.

[keasy]

Why would your ping drop?

Surely you're being routed the same.

Are you comparing to your SH1?

[Enigmo]

Hi,

So I'm new here and not a Virgin customer. However, since my area is a non-fibre area with Openreach, Virgin Media looks like my only shot at internet above 17-24Mbps DL speed and 140KBps upload speed...hence, my interest. But, I've seen so much complaint about Virgin, and have even had a horrible encounter myself with them last year, so I'm being extremely careful before actually phoning them.

I just wanted to ask does this latency issue only affect online gaming? If so, to what degree? Is it bad enough to make the games unplayable? Or is the problem that you can't play at the highest competitive levels? The only game I play online is Tekken 7 on PC--a fighting game--so wondering how that'd be affected compared to FPS games. But, gaming isn't a big concern to me. My priority is downloading and uploading files at high speeds, but not sure if the latency issues will have a big effect.

On another note, I watched a YouTuber ranting about how Virgin capped his internet because he was "using it too much", despite him being on an UNLIMITED bandwidth package...Is this something Virgin really do? How the hell do they get away with it? Does Ofcom have nothing to say about this?

I'm with Sky and if Fibre was available in my area at twice the price of Virgin Media, I would get it based on what I'm seeing about Virgin. Sky doesn't ever disconnect me, never caps my internet and I almost always get the full 24Mbps when downloading. I can also play games online fairly well, unless my brother is playing online on the PS4 at the same time.

[Luke_113]

Hi @Enigmo
So the short answer to your question is both yes and no.
Mostly the Intel Puma 6 issues appear to have been mitigated, the youtuber is likely referring to upload, if you're not on the top tier package or a business package Virgin limit the amount of data you can upload in a period and if you go over that then they cap your upload speed to half, and unless its a tech youtuber, they either probably don't know that, or in all honesty probably don't know what they're talking about. Since the firmware patch I've found Virgin to match and very very very occasionally beat a dsl line in gaming, more often than not its a few ms higher but generally now for me as someone who plays HoTS alot (6000+ games in the last 2-3 years).

That said virtually all ISP provider router modems are utter junk because they're made to a cost, not to a feature set or a certain standard, you only need to look about on the forum to see that alot of people have issues with the wifi, I'm on a business package which is worth the extra IMO, and I run my Hitron (business equivalent of the Hub3) in modem mode with a proper router sat behind it with QoS applied, which means I can max the line (less what I hold back) and still get a stable 20ms ping in a game i.e. hit 180mb/sec download speed and still be playing a game of HoTS fine (HoTS is EXTREMELY sensitive to jitter and lag).

I was in a similar kind of situation that you mention, I only had the option of BT et al, but on Infinity 2 I was only getting about 42mb/s after alot of playing about and fiddling with the connection to get it to be super stable, and managed to get my upload to 6mb/s, switching to Virgin I then got 220mb and 15mb upload (although these days I seem to hit a max of around 13mb) the speed difference is huge, 90Gb GTAV download? no worries down in under 45mins.... Unless you go FTTP you cannot beat Virgin for speed, because of the way that the HFC network works you will get more jitter with cable than DSL (DSL is typical 2-4ms in my experience) and without QoS on Virgin lines will peak upto around 200ms, with QoS switched on I generally hit a max of about 20-30ms (when upload is maxed out) I can get this all the time even when streaming as well.

If you think I'm pandering to Virgin and making out that they have no issues, this is 100% not the case and you're welcome to go back through my post history a few months ago where I was actively advising people not to take Virgin and to leave and break contract via Cisas, I feel comfortable in recommending Virgin again.

If you're actually a pro gamer don't get Virgin or get Virgin as your second connection for big downloads, the house opposite me is a relatively big UK LoL eSports team and thats exactly the setup they have

[cje85]

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@Luke_113 wrote:
@hi @Enigmo
So the short answer to your question is both yes and no.
Mostly the Intel Puma 6 issues appear to have been mitigated, the youtuber is likely referring to upload, if you're not on the top tier package or a business package Virgin limit the amount of data you can upload in a period and if you go over that then they cap your upload speed to half, 

---

Not anymore. The traffic management was scrapped on the same day the new "average speed" advertising came into force. Not reducing the upload speed of heavy users helps to keep the averages looking good. Also the improvements to upstream (more channels, 64QAM modulation) have further reduced the need for traffic management.

https://community.virginmedia.com/t5/Speed/Upload-traffic-Management-removed-on-all-packages/td-p/37...

[Luke_113]

Thanks for the heads up @cje85, wasn't aware of that, no idea what that youtuber that @Enigmo is talking about and probably more likely references connections issues or a local issue during peak time.

[justasking1992]

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@keasy wrote:

Why would your ping drop?

Surely you're being routed the same.

Are you comparing to your SH1?

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Yes I am comparing to my SH1, my ping average is 100% lower compared to when I was using my SH1.. no idea why