RT AC86U - Help me please! Bufferbloat and latency

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slaver01

New Around Here
Hello everyone!
I would like your help to improve my gaming connection.
I have router Asus RT AC86U (ac2900) firmware Merlin 386.2_6. Fibre 1 g/bit with cable connection cat6 only pc. I don't use QoS.

Cattura.PNG


Thanks!!
 

L&LD

Part of the Furniture
Nothing to improve there. You can try the RT-AX86U and see if you see a difference in gaming (and not just in tests).
 

DeepWoods

Occasional Visitor
While those results look bad, in practice you are probably just fine "as is".
Details:
1. With ~900 Mbps down and ~200 Mbps up, it is unlikely that you will ever experience any bufferbloat while gaming. The bufferbloat test is showing you what would happen if you were saturating your up/down limits. You probably aren't hitting those limits, outside of an internet speed test, and therefore under normal use you don't have a bufferbloat problem. Why "fix" a problem only exposed by a test?
2. CakeQoS would very likely solve your bufferbloat problem, and give you an A+ bufferbloat report, at the cost of limiting your download speed to ~300 Mbps. You probably aren't even using 300 Mbps down, with any regularity, so in practice it would be unlikely to hurt. It is easy to turn on CakeQoS with the latest Merlin to conduct the experiment, determine that you could solve your bufferbloat "problem", and then choose to have it on/off. CakeQoS is fantastic for those with lower limits. Most people paying for gigabit service would be saddened to throttle it back to 300 Mbps.
3. You could consider FlexQoS, which will work well above 300 Mbps, but I don't have experience with it.
4. Your unloaded latency of 20 ms is a little bit high, but is likely an artifact of the server selected by the bufferbloat test. What kind of ping do you get from speettest.net?
5. It is very likely that any significant latency in your gaming experience is the result of your service provider, the internet, or the gaming servers (not anything in your house).
5. The RT-AX86U is a great router, but unlikely to change the results of this specific test.
 

heysoundude

Very Senior Member
I'd like to second everything @DeepWoods pointed out, and add this:
look into your MTU, and if you're running Merlin firmware, add ntpMerlin with chrony and find local stratum-1 ntp clocks to sync to.
another possibility to consider is DDNS (and an IPv6 tunnel if your ISP doesn't yet support native ipv6).
 

ColinTaylor

Part of the Furniture
I'd also agree with @L&LD and @DeepWoods that there doesn't seem to be anything to improve here. MTU might be an issue, but it's highly unlikely on a fibre gigabit connection and PMTU. ntp, DDNS and an IPv6 tunnel will not improve your internet connection.
 

slaver01

New Around Here
1. Con ~900 Mbps in calo e ~200 Mbps in aumento, è improbabile che si verifichi un aumento del buffer durante il gioco. Il test del bufferbloat ti mostra cosa accadrebbe se stessi saturando i tuoi limiti su/giù. Probabilmente non stai raggiungendo quei limiti, al di fuori di un test della velocità di Internet, e quindi in condizioni di utilizzo normale non hai un problema di bufferbloat. Perché "risolvere" un problema esposto solo da un test?

If instead at the same time... I play, I use Netflix and various cell phones with youtube. Could I take it all to the limit and have bufferbloat? Could i fix it with flexqos?
 

socaljazzdude

Occasional Visitor
The only thing I would look into is the cable modem.

I started having issues with bufferbloat as well and I also use the 86U. As it turns out, my issue was due to a bad cable modem that was affected by the notorious Puma 6 chipset.

I ended up replacing my old cable modem with a Netgear CM1200 and it got rid of the bufferbloat as well as the random dropped connections on my network.

Not sure if your cable mode is having any issues but thought that was worth mentioning.
 

Steve141

New Around Here
Hello everyone!
I would like your help to improve my gaming connection.
I have router Asus RT AC86U (ac2900) firmware Merlin 386.2_6. Fibre 1 g/bit with cable connection cat6 only pc. I don't use QoS.

View attachment 34998

Thanks!!
enable optimize AMPDU aggregation in wireless settings, if using wireless, this helped me. use QOS maybe?
 

Subkulture

New Around Here
The only thing I would look into is the cable modem.

I started having issues with bufferbloat as well and I also use the 86U. As it turns out, my issue was due to a bad cable modem that was affected by the notorious Puma 6 chipset.

I ended up replacing my old cable modem with a Netgear CM1200 and it got rid of the bufferbloat as well as the random dropped connections on my network.

Not sure if your cable mode is having any issues but thought that was worth mentioning.
Though some ISP’s do not allow switching out the Modem/Router which is one I currently have. That being said bloat/ latency can be greatly reduced by combining the suggestions here Adjust MTU for your network, FlexQOS, Set bandwidth limits to 85% of total upload and download speeds and to my surprise though don’t know why turning on the DNS Filter then setting it to router as well typing in router IP into LAN settings into dns server 1 field.
 

ColinTaylor

Part of the Furniture
... and to my surprise though don’t know why turning on the DNS Filter then setting it to router as well typing in router IP into LAN settings into dns server 1 field.
If that really makes a difference it would suggest that the test site is trying to use DNS to find the closest server and coming up with a different server than before. In which case the test results should not be compared to the previous results.
 

gattaca

Senior Member
^^^ @socaljazzdude is dead on! The "Intel based Puma Chipset" routers are a nightmare of issues. I had one and quickly returned it for a non-Intel-Puma model (Broadcom-based). Just search - there are lists of routers which do not have that awful chipset. Bufferbloat was not the only issue with this design either. Stay safe, stay alive. Peace.
 
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Tech9

Very Senior Member
enable optimize AMPDU aggregation in wireless settings

This may cause issues with time-sensitive applications like games, VoIP, video conference, etc. Not a good advice.

The "Intel based Puma Chipset" routers are a nightmare of issues.

High latency issues were solved/minimized long time ago. I have an Intel Puma 6 modem in use and it works well. You've changed your modem because the ISP allowed you to do so. This is not the case with many ISPs. I don't have that option with mine; I can't use my own equipment on their network.
 

gattaca

Senior Member
^^^ @Tech9 It is my current understanding that Intel "mitigated" some, not all of the issues with the Puma chipsets (5,6,7) via firmware updates. The gotcha there is the ISP must actually update the modem's firmware!

It is unfortunate (SUX really) that in 2021 some ISPs continue prohibiting "bring-your-own-modem"! Sorry man.

Do your own research. Decide if you can provide your own modem, do you want "roll-the-dice" with a Puma 5, 6, 7 based modem?

https://approvedmodems.org/bad-modems/

Stay safe, stay alive! Peace.
 
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socaljazzdude

Occasional Visitor
This may cause issues with time-sensitive applications like games, VoIP, video conference, etc. Not a good advice.



High latency issues were solved/minimized long time ago. I have an Intel Puma 6 modem in use and it works well. You've changed your modem because the ISP allowed you to do so. This is not the case with many ISPs. I don't have that option with mine; I can't use my own equipment on their network.
Regarding firmware updates for Puma 6 modems. This issue wasn’t actually solved. Granted your device may have responded well to the most recent firmware release, but Puma 6 modems still have the flaw regardless.

I thought mine was fine as well until it wasn’t and it became a time bomb of bufferbloat and and disconnects.

The FCC’s rules on bringing your own cable modem are that users can bring their own, however ISP’s are to provide a list of compatible modems. Meaning users are to only use the compatible modems listed from their ISP.

See https://www.congress.gov/bill/116th-congress/house-bill/5035/text

I highly recommend the OP check with their ISP on this since the rules regarding user provided cable modems changed in 2020.
 
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Tech9

Very Senior Member
The FCC’s rules

This is an international forum. You're talking about something US specific. I do have a list of compatible approved modems, but I don't need to purchase my own because the ISP provided one for free is working properly. I don't think the OP has an issue. Bufferbloat in tests at line saturation speeds is normal and expected. With normal real life Internet use he doesn't have bufferbloat. @slaver01 doesn't need to fix anything.
 

socaljazzdude

Occasional Visitor
This is an international forum. You're talking about something US specific. I do have a list of compatible approved modems, but I don't need to purchase my own because the ISP provided one for free is working properly. I don't think the OP has an issue. Bufferbloat in tests at line saturation speeds is normal and expected. With normal real life Internet use he doesn't have bufferbloat. @slaver01 doesn't need to fix anything.
I am aware of that. Although I’m not familiar with the country of origin of the OP, let me just say that if you can use your own modem, you should do so.

Granted, I get what you’re saying that you may not want to buy one if a unit is provided free of charge, users may check out the model of the cable modem provided by their ISP. Your ISP may or may not be providing you with the best modem for you and I highly recommend checking to see if any legacy cable modems that ISP’s are providing are affected by Puma 6.

Bufferloat to the point where it causes service interruptions as a result of a cable modem’s Puma 6 chipset, should absolutely be replaced with a cable modem using a modern DOCISIS 3.1 Broadcom based unit. And for our international users, let me preface if such options are of course available to you.
 

Tech9

Very Senior Member
I am aware of that. Although I’m not familiar with the country of origin of the OP, let me just say that if you can use your own modem, you should do so.

Also US specific, I believe. Is it common in the US to pay modem/router rental fees?
 

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