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]

[dasBOT]

please tell me what is the point of fast download if you can't play the game comfortably after instalation?
if you have slow connection but stable you can do things while downloading then enjoy your online experience, I'm sorry but you can't do that on VM, well you can but you are always handicaped by random latency spikes. My point is you are fine if you didn't try a proper connection but if you did you do realize how bad VM internet is

[RidingTheFlow]

Download speeds are certainly not "mean nothing". It will however depend whether you care about games with online functionality at all. If you play solely single-player offline games - sure, only download speeds matter. Otherwise - lag & jitter will be more important than download speeds. Unless you spend more time downloading games than actually playing them. 

Also, it depends which speeds are you comparing. FTTC xDSL 50~70Mbps speeds from my experience are certainly comfortable enough to be on same level of usability as VM's 150~200Mbps (for same price range). Only when you actually will care for huge bandwidth if you have a big connected family - with many hungry bandwidth users (certainly possible).

So in a nutshell - depends on use case. For small household with significant use of online gaming I certainly can't recommend VM, even if they can deliver advertised speed (as with any ISP they are "up to" and not always actually happen).

[tommey]

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@dasBOT wrote:
please tell me what is the point of fast download if you can't play the game comfortably after instalation?
if you have slow connection but stable you can do things while downloading then enjoy your online experience, I'm sorry but you can't do that on VM, well you can but you are always handicaped by random latency spikes. My point is you are fine if you didn't try a proper connection but if you did you do realize how bad VM internet is

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Could not have said it better myself.

[ShadowOfDeth69]

Mincey is small, insignificant, gay, effeminate, flamboyant, **bleep**y. Depends on context I guess. I used it with the first two and a dash of the third in mind. Never heard it used for "mean" though.

And no, I'm going to go out of my way to download something and record the process. Are you crazy? Took me around 5/6 minutes to download the the GTA Trilogy at just over 7gb in total. You do the math.

[ShadowOfDeth69]

Your original post didn't mention anything about being specific to VM. You made a very general statement that speed means nothing to gamers.

Right now the games I'm playing run perfectly fine with the Hub 3 but I have experienced horrendous lag while playing others. I'm content to keep playing the unaffected games until Virgin release some sort of fix so technically I'm enjoying a reasonable ping of 25-28 to game servers AND awesome DL speeds.

Edit: Obviously you and Tommy here are (quite understandably) bitter with VM right now but just know the problems you're facing might not apply to everyone.

[tommey]

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@ShadowOfDeth69 wrote:
Mincey is small, insignificant, gay, effeminate, flamboyant, **bleep**y. Depends on context I guess. I used it with the first two and a dash of the third in mind. Never heard it used for "mean" though.

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What dictionary gives you that definition? 

Even urban dictionary gives a total different meaning which I am not going to post here

[tommey]

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@ShadowOfDeth69 wrote:

Right now the games I'm playing run perfectly fine with the Hub 3 but I have experienced horrendous lag while playing others. I'm content to keep playing the unaffected games until Virgin release some sort of fix so technically I'm enjoying a reasonable ping of 25-28 to game servers AND awesome DL speeds.

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OK so clearly something is wrong with your connection if the above comment is correct as you should not experience horrendous lag while playing any games not just a select few.

In actual fact you are being limited to what games you can play without experiencing horrendous lag which is unacceptable and you should be getting a discount from VM until it is fixed correct?

[WildWayz]

PS - PSN don't cap speeds. Their network stack sends small packets not large which causes slow downloads. Install a proxy server on the pc and connect your PS4 to that and it will max out the connection

[ShadowOfDeth69]

Ok first off Urban Dictionary is NOT an actual dictionary. You know that right? It's basically the Wikipedia of slang that anyone can upload to and add their own definitions. I know what mincey means in certain context. You're as much an expert on slang as you to seem be on how PSN servers works... Alright? Jesus haha talk about your off topic.

And there's nothing wrong with my connection. In fact it looks to be in far better shape than yours:

https://www.thinkbroadband.com/broadband/monitoring/quality/share/6a115fd02598180be0435242919679cc7a...

I personally don't see the lag people keep talking about but there's still something going on that's affecting some of the games I usually play.

[Stoddy27]

I know these posts are on the gaming forums but we have to keep in mind high latency doesn't just affect gaming. I use VOIP and I can tell you VOIP calls are no fun when experiencing the latency problems of the PUMA6 intel chip. Some people seem to do better than others but maybe these people don't game as much as others? Just a thought. 

Some nights I can be online 15-16ms ping no issues all night some nights I can not play at all 500-600 ms constantly so it really is unpredictable. I do believe VM are doing as much as they can to fix this (without allowing us to use own modems) but I also would say they could offer more communication about this issue and be more interactive with people in this thread. 

A lot of the noise generated from this and calls being put through to their call centres could have been rectified with a short message. "VM will continue to reactivate your old SH2 call 0800 000 000 but we will not activate SH2 purchased from other suppliers. We are working on a fix with Intel / Arris we have been supplied Firmware and we are currently doing a public test with 100 VM users"  There is no excuse for bad customer service no matter the size of the company.

The last thing we need though is to go massively off topic and let VM close this thread. 🙂