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]

[panoSs1]

Well if I have to pay for a new master socket cause provider already in place, and installation not worth test if I am not sure if there will be any problems. Also did everyone before the new firmware update has had latency issues with hub 3? Because I ask a friend in Oxford and tells me he has had no issues in games he play like battlefield. I will ask him to run pingplotter and see for myself

[Sephiroth]

You could not make this up!

Due the IOS 11.4.1 fiasco, the Hub 3 is everyone’s saviour and the best thing since. 

[mitch84]

My Hub 3 in modem mode got updated to .608 last night, was originally on .603.

[gav114]

Mine updated last night. Seems worse off, its a black superhub 3 and now im getting jitter where as before i didnt have that problem. Im on 350vivid and i get on average 306mbps instead of the usual 370+ 2m away from the hub.

Im so sick of this, i do live in a high congestion area but you should get what you pay for. Its not fair to have poor hardware for the price i pay. £48 pounds for broadband without phone line rental or TV.

I've done all the usual stuff like turn off channel optimisation and use channels no one else in my area are using, 4 for 2.4ghz and 40 for 5ghz. if it wasnt for the fact that I cant get fibre from other providers in my area I'd leave in a heartbeat.

[Spitfire16]

Your not alone 

I have also seen a degrade in WiFi Performance since the 608 patch

I've started a new thread about Poor WiFi Speeds since 608 patch

[OllieNZ]

608 also destroyed my WIFI. I was already running some experiments to compare the SH3 to an old Asus RT-N66U and the 9 year old Asus consistently out performed the SH3 both in signal strength (at least 10dbm greater all throughout the house) and quality/stability. Then the update hit and destroyed the WIFI, it was barely usable from any more than 10ft away. Unfortunately for the Asus it's potentially vulnerable to VPNFilter Malware and made a handy short term stopgap but ultimately had to be replaced. Upgraded to a Netgear R7800, I had no idea WIFI could be so good 😄

It's a shame that a product that's touted as a flagship is so bad it's easily out performed by a product that was released nearly a decade ago. The SH3 has destroyed online gaming for me and when my contract is up next month, I'm going to seriously look switching. Been a VM customer 9 years now too.   

[Adduxi]

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@OllieNZ wrote:

608 also destroyed my WIFI. I was already running some experiments to compare the SH3 to an old Asus RT-N66U and the 9 year old Asus consistently out performed the SH3 both in signal strength (at least 10dbm greater all throughout the house) and quality/stability. Then the update hit and destroyed the WIFI, it was barely usable from any more than 10ft away. Unfortunately for the Asus it's potentially vulnerable to VPNFilter Malware and made a handy short term stopgap but ultimately had to be replaced. Upgraded to a Netgear R7800, I had no idea WIFI could be so good 😄

It's a shame that a product that's touted as a flagship is so bad it's easily out performed by a product that was released nearly a decade ago. The SH3 has destroyed online gaming for me and when my contract is up next month, I'm going to seriously look switching. Been a VM customer 9 years now too.   

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In all my (very) long years with NTL/VM I've never used anything but Modem Mode. Before the Hubs, all you had were Modems and they were good.  (RIP VMNG300)  Every Hub in my possession went straight to Modem use, with mostly ASUS Routers flashed with Merlin Firmware. I never had any cause to complain, nor did the kids.

I know people don't like the idea of spending extra money to get decent WIFI, but depending on your particular environment, it's the only way.

Just my tuppence worth  🙂

[OllieNZ]

@Adduxi I don't disagree that there are (and will always be) better products for for WIFI performance than the ISP provided unit but I'm talking about a middle of range unit that's 3 generations old being superior to a current gen unit. If they offered a decent modem only option or if I could replace their junk with my own modem I wouldn't be as annoyed. Even in modem only mode the SH3 leaves a lot to be desired when it comes to gaming and is certainly not even close to being as advertised.  The speeds may be phenomenal but without the stability they're useless for gaming.  

[Guybrush85]

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@OllieNZ wrote:

@Adduxi I don't disagree that there are (and will always be) better products for for WIFI performance than the ISP provided unit but I'm talking about a middle of range unit that's 3 generations old being superior to a current gen unit. If they offered a decent modem only option or if I could replace their junk with my own modem I wouldn't be as annoyed. Even in modem only mode the SH3 leaves a lot to be desired when it comes to gaming and is certainly not even close to being as advertised.  The speeds may be phenomenal but without the stability they're useless for gaming.  

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Tbh a DOCSIS network is never going to be amazing when you're comparing it to other technologies. Cabled in to my router (an R7800 like yours), I find the experience of gaming to be fine for my needs. I've had issues with certain servers, peering type issues, but I can't blame those on the Hub 3. 

Off topic, but if you haven't already then I recommend using Voxels version of Firmware on the R7800. Essentially the same firmware with all packages up to date, some tweaks in settings and option for extra features using Entware.

[rovardi]

I'm in a similar boat. I'm currently on VIVID 100 on a SH1, I've been having ping issues for the best part of 2 years now im assuming due to network congestion in the area (area 30). I play competitive PC games, unstable and high ping is a big no-no and i've suffered enough. I rang to cancel and transfer over to BT but was offered a similar package to mikey but forced onto a SH3. Should I take the offer? Is the SH3 in a spot where competitive gaming is viable or should I just goto BT? (download speed means nothing to me I only want low/stable ping)