c6300 Bufferbloat issues

[chewiegoodie]

Hey All,

So I ran this speed test on my cable connection. I have great results, with the exception of my F in bufferbloat. How do I resolve this bufferbloat issue. The information on DSLReports says to adjust my QoS settings to limit my download and upload to around my connection speeds. The c6300 does not give me control over the QoS settings. Any ideas?

Thanks,

Chewiegoodie

[DarrenM]

Hello Chewiegoodie

Have you tested at another site for bufferbloat? and are you experiencing any issues because of it? hope to hear your feedback

DarrenM

[richbhanover]

Bufferbloat is undesired latency/lag when a router is handling a lot of traffic. It always occurs at the bottleneck link (your cable/DSL connection). 

It is caused by the router forces time sensitive traffic (gaming, Skype, Facetime, VoIP, DNS lookups, etc.) to wait behind large flows of data (downloads, Youtube uploads, etc). You have probably experienced this as laggy, sticky performance when someone else is using the network.

This is a solved problem using the fq_codel algorithm (or others). These have been part of the Linux kernel for over three years. I'm using it with OpenWrt firmware on a Netgear WNDR3800 quite successfully.

@DarrenM: Can you speak to when Netgear might incorporate fq_codel or some other algorithm to combat bufferbloat?

[chewiegoodie]

I work from home and do VOIP and screensharing sessions over GoToMeeting frequently. I have been experience major slowdown issues during these sessions. The most recent time this happened no one else is in the house or using the network. I am trying to rule out everything that could be causing it and this buffer bloat issue is on the list.

[richbhanover]

That would be really frustrating. I'm not sure, though, what you mean by major slowdowns: what do you see? (slow downloads, lag in responses, ?)

[chewiegoodie]

It seems to slow my entire system down to a crawl. Which doesn't seem to point towards a network issue, but my performance counters are not spiking. My CPU utlization is usually around 60% and memory is around the same and I have an SSD which is barely being used at the time.

This is only an issue when I am doing a screen share session. I have had similar issues with sharing over Lync, which is now Skype for Business.

PC Stats:

Intel i7-5600U CPU 2.6GHZ

16GB Ram

500GB SSD

As soon as I stop sharing my screen everything goes back to normal. So I am wondering if this is a bad response by my sharing applications to the buffer bloat issue.

@DarrenM What other buffer bloat evaluation tools would you recommend? I have run it from multiple browsers and with "Private" as well as without. I always receive an F on bufferbloat.

[richbhanover]

Oops. The forum system misfired. Check my next message.

[richbhanover]

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@chewiegoodie wrote:

It seems to slow my entire system down to a crawl. 

>>> Hmmm... Let me ask you to be real specific about what crawls:

>>> Does the pointer on-screen slowly track the motion of the mouse? Is the computer slow to respond to clicks?

>>> Is it slow to open applications/windows? Does other network interaction (what kind) get slow?

Which doesn't seem to point towards a network issue, but my performance counters are not spiking. My CPU utlization is usually around 60% and memory is around the same and I have an SSD which is barely being used at the time.

This is only an issue when I am doing a screen share session. I have had similar issues with sharing over Lync, which is now Skype for Business.

PC Stats:

Intel i7-5600U CPU 2.6GHZ

16GB Ram

500GB SSD

As soon as I stop sharing my screen everything goes back to normal. So I am wondering if this is a bad response by my sharing applications to the buffer bloat issue.

>>> This is a big clue...

@DarrenM What other buffer bloat evaluation tools would you recommend? I have run it from multiple browsers and with "Private" as well as without. I always receive an F on bufferbloat

>>> My next recommendation would be to see what happens to your computer while stressing the network in each direction:

1) In the Command Prompt window, ping google.com - use ping google.com -n 1000 so that it keeps going

2) For the download test, start downloading a big file from your favorite site

3) Notice a) what happens to the ping times? Does the computer slow to a crawl?

4) For the upload test, stop the download, and upload something. The easiest thing is uploading a video to Youtube.

5) Notice the same things as 3) above. 

6) I'd like to know what you find.

NB: This is another form of bufferbloat testing: it is measuring ping times during download or upload.

[chewiegoodie]

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@richbhanover wrote:

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@chewiegoodie wrote:

It seems to slow my entire system down to a crawl. 

>>> Hmmm... Let me ask you to be real specific about what crawls:

>>> Does the pointer on-screen slowly track the motion of the mouse? Is the computer slow to respond to clicks?

>>> Is it slow to open applications/windows? Does other network interaction (what kind) get slow?

The mouse jumps around the screen and takes a very long time to respond to clicks between browser tabs or different windows. Scrolling takes about 10 seconds to scroll 1 line in a browser window even if the page was already loaded. And you can forget about launching new applications even lightweight ones like notepad.

Which doesn't seem to point towards a network issue, but my performance counters are not spiking. My CPU utlization is usually around 60% and memory is around the same and I have an SSD which is barely being used at the time.

This is only an issue when I am doing a screen share session. I have had similar issues with sharing over Lync, which is now Skype for Business.

PC Stats:

Intel i7-5600U CPU 2.6GHZ

16GB Ram

500GB SSD

As soon as I stop sharing my screen everything goes back to normal. So I am wondering if this is a bad response by my sharing applications to the buffer bloat issue.

>>> This is a big clue...

@DarrenM What other buffer bloat evaluation tools would you recommend? I have run it from multiple browsers and with "Private" as well as without. I always receive an F on bufferbloat

>>> My next recommendation would be to see what happens to your computer while stressing the network in each direction:

1) In the Command Prompt window, ping google.com - use ping google.com -n 1000 so that it keeps going

2) For the download test, start downloading a big file from your favorite site

3) Notice a) what happens to the ping times? Does the computer slow to a crawl?

4) For the upload test, stop the download, and upload something. The easiest thing is uploading a video to Youtube.

5) Notice the same things as 3) above. 

6) I'd like to know what you find.

Started the ping test and was consistently getting 20-40ms response times.

Started to DL a 20gig file from my cloud hosted sharepoint site and pings grew to mostly 100-300ms occasionally a 30-99ms would sneak in as well.

Cancelled the DL and immediately back to 20-40ms response times.

NB: This is another form of bufferbloat testing: it is measuring ping times during download or upload.

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[chewiegoodie]

For more concrete statistics.

No dl:

Ping statistics for 173.194.115.73:
Packets: Sent = 1000, Received = 1000, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 26ms, Maximum = 147ms, Average = 34ms

During dl:

Ping statistics for 173.194.115.73:

Packets: Sent = 1000, Received = 1000, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 27ms, Maximum = 885ms, Average = 131ms

[richbhanover]

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@chewiegoodie wrote:

For more concrete statistics.

No dl:

Ping statistics for 173.194.115.73:
Packets: Sent = 1000, Received = 1000, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 26ms, Maximum = 147ms, Average = 34ms

During dl:

Ping statistics for 173.194.115.73:

Packets: Sent = 1000, Received = 1000, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 27ms, Maximum = 885ms, Average = 131ms

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re: System slowing to a crawl... Yikes! That's definitely a crawl - the entire system has been slowed, not just network stuff.

There's definitely a touch of bufferbloat, but I that certainly wouldn't cause that much of a crawl: your mouse jumping around, the slow to respond to clicks, etc. 

In the absence of other's recommendations, I would contact the support folks with your screen sharing software to get their advice. I would love to hear their advice and if that fixes it.

[chewiegoodie]

A touch of buffer bloat? The dslreports test shows a much higher ping slowdown under their simulated load of 1500ms. My rigged together test may show closer to real world results. However, they are still unacceptable.

Look if I want to put my kids in front of a Netflix movie for a couple hours to try to get a break and decide to spend it playing a video game online, I do not want to see a 3-5X increase in my ping as a result. 

I would consider this a defective product and would have already returned it, if it wasn't past Amazon's return window.

I don't care if it is actually the cause of my problem. I want to resolve the defect and then move on to the next possible issue.

[richbhanover]

I am sorry that you're having such poor performance on your network, but I was just offering advice re: bufferbloat, and not associated with any of the gear you're using. As I re-read this thread, I see you have three sources of redress:

- You can call the Netgear support folks, and say that your router isn't working well. Ask if you can get a replacement - you may still be within the warranty period even though you can't send it back to Amazon.

- Your screen sharing software is still suspect. You describe that using it causes your computer to become catatonic.

- You could also contact Comcast to see if they can offer a better cable modem - the DOCSIS 3.1 standard has built-in fix for bufferbloat.

I wish you the best...

[chewiegoodie]

@richbhanover Obviously it is not your fault. I shouldn't bite your head off for it especially when you are just trying to help.

I am focusing on one problem at a time, currently bufferbloat. Since, if I contact the support for the screen sharing software I am concerned they will point to any network issues that might turn up during any troubleshooting process.

I guess I wanted someone from Netgear to give me some sort of hope of new firmware in the pipe. Ugh!

What kills me is the "low cost alternative" of their cable modem router the N450 has the QoS features that could allow me to put a hack in place.  My guess is the AC chipset didn't include QoS but the N, being out longer, does include it.

[richbhanover]

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@chewiegoodie wrote:

@richbhanover Obviously it is not your fault. I shouldn't bite your head off for it especially when you are just trying to help.

🙂

I am focusing on one problem at a time, currently bufferbloat. Since, if I contact the support for the screen sharing software I am concerned they will point to any network issues that might turn up during any troubleshooting process.

I would be tempted to attack this the other way around. 50% of the world (actually, way more) has bufferbloat, and what you're seeing isn't that bad. I can't imagine that it's causing the profound slowness you're seeing. Fixing the bufferbloat would require replacing the router anyway (since there are no bufferbloat settings in the current one.)

I am deeply suspicious of the screen sharing software (what brand do you use?) since the dreadful performance seems to be correlated with its use. If you call their tech support folks, you can tell them what some other speed test shows (say, http://speedtest.net ) - the line is plenty fast. (Don't talk about the bufferbloat. They won't know what it is, it won't be in their scripts, but it would give them a reason to throw the problem back to you.)

I guess I wanted someone from Netgear to give me some sort of hope of new firmware in the pipe. Ugh!

That sure would be nice, but the Netgear Moderators seem to throw out a good word, but then scurry away if they get an inconvenient response (as happened with this thread).

What kills me is the "low cost alternative" of their cable modem router the N450 has the QoS features that could allow me to put a hack in place.  My guess is the AC chipset didn't include QoS but the N, being out longer, does include it.

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Find an 800-number for Netgear support and call them. Tell them you've asked on the forums, and not got any satisfaction. Would you be satisfied with the N450 router? Offer to trade...