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]

[wotusaw]

chrisxp said:

"Hi guys,

Done a puma6 test and got these results on a SH3 with 300/20 connection. Is there any cause for concern?"

Yours is better than my 200/20 gamer(lol u r joking ain't ya!) package. Mine has about 15 red dots on average everytime. It should be all green, or mostly, btw.

The 'Broadband' widget test will probably be almost solid yellow though. It's very pretty.

You will only really notice this in gaming if you play something like COD or Titanfall 2 (livefire, pilot vs pilot modes) and similiar shooters. Face to face against another player you WILL lose as effectively your button press takes twice as long. A button press takes about 200ms on average. The glorious HUB3 adds another random 250ms, I think in 2 second cycles...a boffin is welcome to correct me there if I'm wrong.

This is a test I use in gaming mice reviews.....https://www.humanbenchmark.com/tests/reactiontime

On web pages there are delays but these vary. It now takes THREE seconds to load my clansite pages on the HUB3 where before on the HUB2 it took none.

I'm waiting for a fix from Virgin via Intel/whoever like everyone else.

Will I go over to BT Infinity 2 at 76mb?=Not sure. I hate BT with a passion(don't ask).But as the months go by it get's more likely. I've been a Virgin customer since before the Earth cooled down, btw.

Do Virgin care if I or any of us leave them?=I'd like to think so but really get the feeling they operate like car salesmen/women....ie: There will be another mug along in a minute or two....just wait it out.

[RidingTheFlow]

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@mrfreeman wrote:

Virgin Media have completely lost it.  Do you think this is Richard Branson's revenge for Brexit?  He was mightily cheesed off about Britons voting leave, I am convinced this is his payback.  Only problem is, it will backfire on him big-time.  I do sympathise with his island property damage from Irma though, and his son is being extremely helpful in the relief effort out there.  I just wish he would spend more effort on addressing this rather major problem aswell (he probably thinks this broadband thing is trivial compared to the damage out there unsurprisingly).  

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Oh but he washed his hands of Virgin Media (sold his stake) quite a while ago. Good entrepreneur always have a good feeling when its important to jump ship before it starts to sink 😉

[RidingTheFlow]

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@wotusaw wrote:

Will I go over to BT Infinity 2 at 76mb?=Not sure. I hate BT with a passion(don't ask).But as the months go by it get's more likely. I've been a Virgin customer since before the Earth cooled down, btw.

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Surely as long as you have FTTC in you area you should be able to get fibre package from any other loop-unbundled ISP, like Plusnet, Sky, etc?

[Drewley]

@RidingTheFlow

Thanks!

Yeah, not really sure why, all I know is it's loads better!

[wotusaw]

RidingTheFlow said:

"Oh but he washed his hands off Virgin Media (sold his stake) quite a while ago. Good entrepreneur always have a good feeling when its important to jump ship before it starts to sink "

He only owns 10% now.

Virgin are in ter-rouble and 'pumagate' is the last thing they need right now.

Personally I could not have seen this coming. Had no idea modems were soooo complicated.

BT Infinity is looking more attractive as I believe you can use your own modem? Just threw that in as a conversation starter, btw.

RidingTheFlow said:

"Surely as long as you have FTTC in you area you should be able to get fibre package from any other loop-unbundled ISP, like Plusnet, Sky, etc?"

Really don't want to leave Virgin. I'm aware of all the other options. I'm on a contract till Feb 2018. My plan is to wait to see if the 'fix' works in quarter 4. Maybe by Feb 2018 there will be news about the HUB4. If it all goes kerfooey then regretfully it will be Openreach ultrafast fibre if available.

Sky seem to be rather like Virgin but more 'wolflike'. I talked to a couple of their reps one saturday at Morrisons and they did seem to me to be like a couple of laughing hyenas.

[RidingTheFlow]

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@wotusaw wrote:

RidingTheFlow said:

BT Infinity is looking more attractive as I believe you can use your own modem? Just threw that in as a conversation starter, btw.

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Yes, you can. Either modem or even powerful router with integrated VDSL modem, e.g. https://www.amazon.co.uk/dp/B01CSDM6LW/ref=cm_sw_r_tw_dp_x_G5TUzbDF6517J

[chrisxp]

Hi wotusaw,

I didn't realise I was better than other connections, my puma test did show many red a few months ago.. Was there a firmware rollout as I have seen better results?

I play Battlefield 1, and don't see any handicap to myself in the game, FPS & ping are fine and my shots all connect.

My graph is mostly yellow but unlike any others that have posted.

See here:
https://www.thinkbroadband.com/broadband/monitoring/quality/share/63279474640229b482b4561b3ecd8defa8...

Does the graph look OK or should I try to get a SH2AC like others?

[RidingTheFlow]

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@chrisxp wrote:

I play Battlefield 1, and don't see any handicap to myself in the game, FPS & ping are fine and my shots all connect.

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You hit every shot? Wow, but I am not going to believe it 😉

However if you think its working fine for you - that's most important, don't bother and stay on SH3.

[wotusaw]

chrisxp wrote:

"Does the graph look OK or should I try to get a SH2AC like others?"

Yours is much better actually. Not as good as the SH2ac but alot better than the 200/20mb gamer package. I can't see 330/20mb package on my Virgin page yet so presume not available in my area yet? I'd get that just for a quick temp half fix.

I've seen other 300/20 graphs and they are similiar to yours. Basically half the pretty yellow of the 200/20 gamer(lol u r kidding!) package.

I used to play Battlefield but went over to Titanfall 2. Just because my clan plays that one mostly. If your a sniper then this won't effect you much. It's the lightning face to face stuff where the pain is felt mostly. I'm an average player prone to fits of rage and biting things.. Possibly the better you are the less the pain anyway.

[eddiechatburn]

Just to follow up, there was an activation issue preventing new connections, but this cleared last night so I am now up and running.

To cap it all, an engineer was sent to me yesterday, who arrived with another 2ac - which he duly left with me.

Then this morning the promised 2ac shipped by retentions on Monday arrived, which turned out to actually be a 2ac!!

So I now have my Hub 3, disconnected, 😀 a 2ac running Vivid 200 gamer, and 2 spare 2ac's as well.

Looks like Virgin have hired ex- British Rail people to resolve the issue.

Seriously, though, don't give up! And if any of you can talk retentions into arranging either of these spare units to be sent to you, get on with it and let me know!!