cancel
Showing results for 
Search instead for 
Did you mean: 

Hub 3 / Compal CH7465-LG (TG2492LG) and CGNV4 Latency Cause

Datalink
Up to speed

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]

4,478 REPLIES 4,478


@RidingTheFlow wrote:

shane, seriously, can you learn how not to quote the whole page of posts? It gets tiring to see the wall of text you've quoted followed by another wall of text that you keep generating.

And yes, the behind-the-doors situations what went with trials and internal discussions with whole Puma 6 fiasco you describe are plausible, but that's about it. This is just one of possible scenarios which could've transpired - but there are other possibilities, which could've lead to same observed situation. Don't try to act like you have insider knowledge of what actually happened, because you don't, and your massive amounts of same text are still a pointless speculation from your part (even if plausible). Reposting it multiple time in authoritative manner does not make it any more true, since it remains an armchair analyst theory based on circumstantial evidence - therefore any critical-thinking person would not take it as gospel to act solely on it.

 


Compared to the only other "theory" being suggested here its infinitely more likely than VM deliberately pushing through a known faulty device with a known fault they knew wouldn't be fixed 😛

Either way, i've provided the logic behind the reasons i give, you can choose to do as you wish with that information, at the end of the day it won't change your available options

wotusaw
Superfast

A bit off topic but thought I'd just let you know. I've changed up to Virgin 300 Vivid gamer and immediately noticed a huge improvement.

I did the tests and at first glance the broadband widgets didn't look any different until they were stretched out then it can be seen that less latency is coming through on the 300 Vivid.

I posted some pics here to show this..http://thenitwitts.enjin.com/forum/m/28206608/viewthread/30983339-virgin-300-vivid-gamer-maybe-good-...

This site(my clansite) took 2/3 seconds to load before on the 200 Vivid gamer and really drove me nuts.

Now on the 300 Vivid gamer it's instant. Also Titanfall 2 plays incredibly well now. I have no whinges to throw at the HUB 3 anymore.

I'm puzzled because there's still alot of yellow going on. However there's been a massive improvement. Far more than the tests would suggest.

Logic would suggest the more that's thrown at the HUB 3 the more it would surrender and die. This doesn't from my subjective gaming tests, seem to be the case.

Any explanations? Or am I just a deluded, erm, dotard.(Don't think anyone's used 'dotard' for at least 100 years):smileyhappy:

 

Sounds like problem you had wasn't entirely due to SH3, but something more serious (misconfiguration maybe?).

When I had SH3 I didn't have any noticeable slowdowns in loading websites or having games unplayable.

 

imzrex
Dialled in

Whats the news on the Hub 3 is it still dead in the water or is there an update, I am currently still on the Hub 2ac but have a Hub 3 new in the box worth switching it out yet?

horseman
Alessandro Volta

@imzrex wrote:

Whats the news on the Hub 3 is it still dead in the water or is there an update, I am currently still on the Hub 2ac but have a Hub 3 new in the box worth switching it out yet?


SH3 still hibernating on current (year old) V9.1.116V firmware with no official response to-date.   Switching for you takes a simple phone call(if auto registering doesn't work) but likely your shipped SH3 is on 88T and may take a couple of hours to auto-update to 116V after it's activated/registered. 

Whether you swap to SH3 depends on your usage profile/LAN configuration.  The basic differences (in addition to the Puma6 hyperbole on this/other threads) is that SH3 can tune to upto 24 downstream channels and therefore take advantage of inherent DOCSIS "load balancing"   of  300/350 (and future) premium Tiers.   The SH2AC legacy tuning to 8 D/S channels means VM will only configure upto max V200 Tiers  that are also manually "load balanced" in groups of 8 D/S channels across node's/cable segments potential  24channels (if you're area is upgraded).  

That could cause some temporary "utilisation" issues with sporadic unbalanced network demand which is why  VM is encouraging migration from legacy SH2 Hubs to SH3 which gives more efficient use of current cable RF spectrum.  Managing the "Gaming" issues is entirely another matter of course! 😞  

Regards Tony
"Life is a Binary Inspired Turing Computed Hologram"(don't PM or @Mention me - in case ignoring you offends)
DEFROCKED


@imzrex wrote:

Whats the news on the Hub 3 is it still dead in the water or is there an update, I am currently still on the Hub 2ac but have a Hub 3 new in the box worth switching it out yet?


There is no update. Not worth switching, unless you are having problems with current hub.

My current Graph Screenshot_1.png

 

 

This forum thread started on ‎02 December 2016. It has been 298 days or 9 months, 24 days since then.

There's still no sign of a firmware fix to be provided by VM.

Surely 298 days is enough time to arrange new hardware/apply the existing firmware fixes/change policy to allow other modems/anything else

What say you VM - will this be fixed and when exactly?? 

Answers only accepted from people speaking directly on VM's behalf ,so that should exclude a certain someone who comments on everyone's post.

I expect to hear silence if that is the case VM would silently be confirming there is no plan to implement a fix at present and anyone on the Gamer package should be able to get compensation for a reduced service.

p.s. only 173 pages of complaints so far, does it need to hit 200+ before a proper official comment?

 

 

Stythinator
Problem sorter

is this problem only happening with people on the Gamer Package then? What about the original 200mbps service?

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media.

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks.

Its affects everyone who has a Superhub 3, but gamers are the ones who notice it due to the SH3 causing the latency issues etc.