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]

[yabba]

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@tonycv51 wrote:

I genuinely puzzled why people on here refer to the firmware as “trial”. It’s clearly standard for new and upgrading 350 customers, so is production firmware as it’s now standard for a segment of VM customers beyond triallists.  The only trial is the one of VM customers patience  with a lack of information on what appears to be a very slow / pro-longed rollout  

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Because it is a trial. It'll stop being a trial when they roll it out to everyone. The fact that people on a trail have the firmware doesn't make it 'standard' - quite the opposite.

They should have already rolled it out everywhere. I would just sit and fire them one by one until they had. Get these buffoons out of the company and to a fast food restaurant where they belong.

The .603 firmware cannot be worse than the 116v - and, clearly whatever process these buffoons believe having a "trial" helps we know it does nothing at all, nothing, to improve the quality of their products. Because otherwise we wouldn't all have superhub3s with 116v on them would we? Anyone involved in rolling out 116v, purchasing sh3 or delaying this new firmware should be using a mop and bucket to clean the toilets.

[dacra]

[url=https://www.thinkbroadband.com/broadband/monitoring/quality/share/46ffe6ab788cc71516b52c057e1adc37f0...]

[dacra]

Here's my graph, don't really know what this means but worried as a new VM 100 customer who hasn't tried gaming yet (busy Bank hol!) 

[jonathanm]

From a customer perspective I agree and want the updates too. However, being in software engineering (and technically this if in the hardware space so much greater possibility of bricking customer equipment) the approach albeit perhaps slower that say your computer, is relatively forward leaning. From following these forums and not being on any trials I think there has been at last three new firmware updates in the last six or so months. The question really lies in whether any of them could have been release candidates in they're own right to provide incremental improvements to aspects along the way.

I think this could only work though with more open communications about the work behind the scenes, keeping schtum and dropping only a partial fix, even with more on the way, would likely only a stoked the fires for floods of further complaint in the interim.

[philjohn]

That's a pretty good BQM for the V firmware.

[Andrew-G]

"From following these forums and not being on any trials I think there has been at last three new firmware updates in the last six or so months"

Press reports stated that Intel had released their Puma 6 patch to Arris in late 2016.  Making the possibly incorrect assumption that both Intel and Arris are suitably embarrassed to put the effort in to knowing how their kit works, and rolling out a fix, why is it that Vermin Media's horrible, cheap own brand Hub 3 takes a further year and a half, still without any sight of a full release candidate?  

As yabba put it above, VM's management should be cleaning toilets.  And even then I wouldn't trust them to do a timely and competent job.

[SHRAMB0]

Hi,

Do we know when/if to expect a fix?

I've been having issues for months and discovered the Puma 6 related issue last night, so I believe I have fallen victim to it.

Riot Games' support told me the issue was on Virgin Media's end, but it took us 5 days to get in contact with Virgin's technical support, who ignored everything we said and told us to simply turn it off and back on again.
My main issue right now is that I can't play basic games. I pay for Xbox Live Gold, but cannot play a single game of Overwatch without being disconnected from the server.

I am basically losing money due to this issue, so could really do with the fix now.

[tommey]

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@SHRAMB0 wrote:

Hi,

My main issue right now is that I can't play basic games. I pay for Xbox Live Gold, but cannot play a single game of Overwatch without being disconnected from the server.

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Sounds like something else is going on with your connection, setup a BQM if you have not done so already and post it here, you may also want to check your connection stats for any signs of power issues, if you are using WiFi to connect to the router then grab a cable instead.

[jonathanm]

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@Andrew-G wrote:

As yabba put it above, VM's management should be cleaning toilets.  And even then I wouldn't trust them to do a timely and competent job.

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I just think it's important to clearly differentiate between management and firmware engineers, if anything like people I know they'll have been  eager to get updates out as software/firmware sat on the shelf doesn't benefit anyone!

[Luke_113]

So Business users are having an unannounced outage this evening and next Tuesday night/Wednesday morning as VMB are starting to rollout the equivalent new firmware, I had it for a week or so before I was upgraded again (via unannounced downtime) to an even newer firmware that borked my connection as with a lot of other VMB users aswell but a power off and on again fixed it. So potentially I believe that could also herald the rollout to consumers on less than 350mb connections, thought I have absolutely nothing to go on to confirm that, will post some before latency graphs later when I’m home