Home News Forum Articles
  Welcome back Join CF
You are here You are here: Home | Forum | Ping skyrockets + Packet Loss when Uploading

You are currently viewing our boards as a guest which gives you limited access to view most of the discussions, articles and other free features. By joining our Virgin Media community you will have full access to all discussions, be able to view and post threads, communicate privately with other members (PM), respond to polls, upload your own images/photos, and access many other special features. Registration is fast, simple and absolutely free so please join our community today.


Welcome to Cable Forum
Go Back   Cable Forum > Virgin Media Services > Virgin Media Internet Service

Ping skyrockets + Packet Loss when Uploading
Reply
 
Thread Tools
Old 26-07-2020, 18:48   #1
oscarandjo
cf.member
 
Join Date: May 2020
Posts: 22
oscarandjo is an unknown quantity at this point
Ping skyrockets + Packet Loss when Uploading

I'm posting this on behalf of a friend who I've been having a nightmare playing online games with recently because of his Virgin Media connection.

Essentially, whenever he's doing an upload his ping spikes up massively, and he gets packet loss. These uploads are capped at 1MB/s so aren't maxing-out his bandwidth (in speedtests he gets 12Mbps upload).

See BQM:


You can see at 6pm he has some uploads running and the average pings spike up to the 160ms range. More worryingly, you can see some red packet loss.

I asked him to show me the Downstream and Upstream pages on the router.
Note, the "Pre RS Errors" and "Post RS Errors" were after about an hour from last rebooting the router.

Downstream:


Upstream:


Any idea what the cause of this issue might be? Is this the famous bufferbloat issue on underpowered routers?
oscarandjo is offline   Reply With Quote
Advertisement
Old 26-07-2020, 21:36   #2
Kushan
FORMER Virgin Media Staff
 
Kushan's Avatar
 
Join Date: Dec 2010
Location: Warrington
Posts: 4,665
Kushan has a bronze arrayKushan has a bronze arrayKushan has a bronze array
Kushan has a bronze array
Re: Ping skyrockets + Packet Loss when Uploading

1MB/s = 8Mbit + overheads, so it doesn't surprise me his ping skyrockets when he's uploading files, if his max upload speed is 12mbit.

But that doesn't sound right, either. What's his actual Virgin package and what's his modem provisioned to? If he's on 100Mb, his max upload is actually 10mbit, not 12. If he's on 200, it should be 20, 350 should be 35. Something doesn't check out.
__________________
My views are my own and in no way reflect those of Virgin Media.
Kushan is offline   Reply With Quote
Old 26-07-2020, 22:21   #3
Paul
Dr Pepper Addict
Cable Forum Team
 
Paul's Avatar
 
Join Date: Oct 2003
Location: Nottingham
Services: VM Phone : Sky Mobile : Sky TV : VM BB (350 Mbps) : Vodafone BB (38 Mbps)
Posts: 22,577
Paul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered stars
Paul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered stars
Re: Ping skyrockets + Packet Loss when Uploading

Presumably the 10M upload is over provisioned, so may read as up to 12 on a speed test.

However, it doesnt matter, uploading at you max speed is going to kill pings, regardless of what that max is.
__________________

Baby, I was born this way.
Paul is offline   Reply With Quote
Old 27-07-2020, 09:05   #4
oscarandjo
cf.member
 
Join Date: May 2020
Posts: 22
oscarandjo is an unknown quantity at this point
Re: Ping skyrockets + Packet Loss when Uploading

The rule of thumb I'd read is you should cap uploads to 80% of your upload speed, so I just suggested he do a speedtest (which was 12Mbps), then 80% is 9.6Mbps, which was reduced to 8Mbps for some leeway. I will suggest he reduces this even more.

I understand maxing out your download/upload will affect pings, but it surely shouldn't cause packet loss?

This is my home connection (VM 200Mbps), I run PC backups which take a few days to complete. There is no upload bandwidth limit imposed, meaning it saturates my upload bandwidth.
My BQM chart shows rises in ping, but not to the same extreme, and there is no packet loss (my backup finished at 2pm here):


Compare this to my friend's BQM chart, even with a bandwidth limit imposed there are much higher average pings and even some packet loss.


Are the number of "Post RS Errors" on Downstream Channels 1-4 (but not 5-8) normal on my friend's router?
oscarandjo is offline   Reply With Quote
Old 27-07-2020, 10:48   #5
General Maximus
C/O Felix Legion
 
General Maximus's Avatar
 
Join Date: Nov 2008
Location: Lincoln
Services: phone + L TV + 350mbit BB + Sky+HD
Posts: 9,146
General Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronze
General Maximus is cast in bronzeGeneral Maximus is cast in bronze
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by oscarandjo View Post
Are the number of "Post RS Errors" on Downstream Channels 1-4 (but not 5-8) normal on my friend's router?
no, you shouldnt be getting the T3 timeouts on the upstream either. Click on reset counters on the post-rs errors and reboot the shub and see what happens.
__________________
Join the Mockingjay, join the fight
General Maximus is offline   Reply With Quote
Old 27-07-2020, 10:53   #6
oscarandjo
cf.member
 
Join Date: May 2020
Posts: 22
oscarandjo is an unknown quantity at this point
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by General Maximus View Post
no, you shouldnt be getting the T3 timeouts on the upstream either. Click on reset counters on the post-rs errors and reboot the shub and see what happens.
These screenshots were taken about an hour after rebooting the shub, which I believe resets these numbers. But I will continue to monitor it.

What causes these timeouts? The power levels look in-spec (upstream power looks of 48-49 is borderline from what I've read) and SNR looks about right too.
oscarandjo is offline   Reply With Quote
Old 27-07-2020, 11:09   #7
General Maximus
C/O Felix Legion
 
General Maximus's Avatar
 
Join Date: Nov 2008
Location: Lincoln
Services: phone + L TV + 350mbit BB + Sky+HD
Posts: 9,146
General Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronze
General Maximus is cast in bronzeGeneral Maximus is cast in bronze
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by oscarandjo View Post
What causes these timeouts? The power levels look in-spec (upstream power looks of 48-49 is borderline from what I've read) and SNR looks about right too.
48 is mint and mine has been 48 since the dawn of time. There can be several different types of problems with upstream channels which is why there are the 4 different T levels and depending on what the problem is it can impact the downstream and make it looks like there is a downstream fault when there isnt one.
__________________
Join the Mockingjay, join the fight
General Maximus is offline   Reply With Quote
Old 27-07-2020, 16:23   #8
roughbeast
cf.mega poster
 
roughbeast's Avatar
 
Join Date: Jul 2008
Location: Coventry Cab CV829
Services: 1GB /50mb, TV V6x2, Phone XL Talk unlimited and mobile x4
Posts: 1,570
roughbeast has reached the bronze age
roughbeast has reached the bronze ageroughbeast has reached the bronze ageroughbeast has reached the bronze age
Re: Ping skyrockets + Packet Loss when Uploading

This graph shows my system (170Gb) being backed up to Acronis Cloud between about 02:30 and 04:00 last Sunday morning. (uncapped upload) Upload speed for this backup tends to be in the range 30-45 Mbps out of the over-provisioned 50Mbps I pay for. This is the kind graph profile I would expect from a decently performing connection. I would agree that the graph in the OP isn't satisfactory.

__________________
Join Date: Jul 2008
Location: Coventry Cab CV829
Services: 1Gb /50Mb, V6 box X2, Phone XL Talk unlimited and mobile x4. SH4 in modem mode with GT-AX11000
roughbeast is offline   Reply With Quote
Old 27-07-2020, 17:16   #9
Kushan
FORMER Virgin Media Staff
 
Kushan's Avatar
 
Join Date: Dec 2010
Location: Warrington
Posts: 4,665
Kushan has a bronze arrayKushan has a bronze arrayKushan has a bronze array
Kushan has a bronze array
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by oscarandjo View Post
I understand maxing out your download/upload will affect pings, but it surely shouldn't cause packet loss?
Are you and your friend both using the same Hub?
Are you both using the hub in hub mode, or router or what?
If so, do you have the same router?

Is your friend actually experiencing packet loss? The TBB graph is only showing that the ping request didn't get a response, this can happen with some setups when the connection is being throttled, as IPMC responses are fairly low in the priority.
__________________
My views are my own and in no way reflect those of Virgin Media.
Kushan is offline   Reply With Quote
Old 28-07-2020, 23:19   #10
oscarandjo
cf.member
 
Join Date: May 2020
Posts: 22
oscarandjo is an unknown quantity at this point
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by Kushan View Post
Are you and your friend both using the same Hub?
Are you both using the hub in hub mode, or router or what?
If so, do you have the same router?

Is your friend actually experiencing packet loss? The TBB graph is only showing that the ping request didn't get a response, this can happen with some setups when the connection is being throttled, as IPMC responses are fairly low in the priority.
No, we live at different houses, but are just playing video games on the internet together.

Both hubs are in router mode, I have the SH3 and my friend (with the connection problems) has the SH2ac.

Interesting theory about the IPMC responses.
oscarandjo is offline   Reply With Quote
Old 28-07-2020, 23:25   #11
General Maximus
C/O Felix Legion
 
General Maximus's Avatar
 
Join Date: Nov 2008
Location: Lincoln
Services: phone + L TV + 350mbit BB + Sky+HD
Posts: 9,146
General Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronzeGeneral Maximus is cast in bronze
General Maximus is cast in bronzeGeneral Maximus is cast in bronze
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by oscarandjo View Post
IPMC responses.
ICMP
__________________
Join the Mockingjay, join the fight
General Maximus is offline   Reply With Quote
Old 29-07-2020, 14:34   #12
Paul
Dr Pepper Addict
Cable Forum Team
 
Paul's Avatar
 
Join Date: Oct 2003
Location: Nottingham
Services: VM Phone : Sky Mobile : Sky TV : VM BB (350 Mbps) : Vodafone BB (38 Mbps)
Posts: 22,577
Paul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered stars
Paul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered starsPaul is seeing silvered stars
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by oscarandjo View Post
Interesting theory about the IPMC responses.
Its not a theory.

Routers treat ICMP (pings) as low priority, so when they get busy, they can end up just ignoring/dropping them.
__________________

Baby, I was born this way.
Paul is offline   Reply With Quote
Old 29-07-2020, 15:08   #13
roughbeast
cf.mega poster
 
roughbeast's Avatar
 
Join Date: Jul 2008
Location: Coventry Cab CV829
Services: 1GB /50mb, TV V6x2, Phone XL Talk unlimited and mobile x4
Posts: 1,570
roughbeast has reached the bronze age
roughbeast has reached the bronze ageroughbeast has reached the bronze ageroughbeast has reached the bronze age
Re: Ping skyrockets + Packet Loss when Uploading

Quote:
Originally Posted by Paul View Post
Its not a theory.

Routers treat ICMP (pings) as low priority, so when they get busy, they can end up just ignoring/dropping them.
theory = explanation
__________________
Join Date: Jul 2008
Location: Coventry Cab CV829
Services: 1Gb /50Mb, V6 box X2, Phone XL Talk unlimited and mobile x4. SH4 in modem mode with GT-AX11000
roughbeast is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 22:42.


Server: curium.zmnt.uk
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.