Poor single thread speed on Virgin

So I'll try to be brief but this is a problem I've been having for many months on Virgin, and it seems I'm not alone in that it's gotten worse since the VIVID 'upgrade'.

Basically, single-thread speeds are woeful around peak times but as others have found, Virgin refuse to accept anything but speedtest.net for diagnostics.

This is what peak time looks like for me: http://www.thinkbroadband.com/speedtest/results.html...

Vs off-peak: http://www.thinkbroadband.com/speedtest/results.html...

Obviously I've checked using far more that just the TBB tester and this is fully reperasentaitive of the real-world HTTP/FTP download speeds I'm getting.

I'm having an infuriatingly hard time getting VM to acknowledge a problem, let alone begin to investigate it, so I'm just wondering if anyone has had any success in getting this sort of issue resolved? Feel free to ask for any more details, I just don't want to make the first post a huge wall of text.

Many Thanks!

Since speedtest.net usually uses 8 threads it will of course give a good result even when people have congestion, hence why providers like it so much.

Alas on cable networks contention is a lot more visible than the DSL products

Any idea if there's a way to get it resolved? I've been back and forth with tech support, the forums and now the complaints team and I'm getting nowhere, I just keep getting told that no fault is showing on their network.

I noticed you responded to a similar thread and I wonder if it could be something similar causing it? http://forums.thinkbroadband.com/virgin_cable/t/4465...

Or is it one of those things they'll refuse to acknowledge so I'll just have to put up with unless it coincidentally gets resolved one day?

Here's another speed test from right now: http://www.thinkbroadband.com/speedtest/results.html...

I think the way they're handling it i.e. implying I'm making it up or something, is annoying me almost as much as the problem itself now!

Thanks very much for replying!

As this issue 'corrects' itself at off peak times it is not a configuration issue, but simply that congestion is rearing its ugly head in your area.

At some point it will get so bad that Virgin Media will do something to add more capacity in the area, or the small number of people downloading the Internet library will stop.

I think you may find this is 'by design'.

The more modern CMTS equipment can implement a QOS known as Weighted Fair Queuing. This de-prioritises packets of continuous streams.

On an uncongested cable segment this has no impact to speed.
However as congestion increases, the deprioritised packets get delayed / dropped and TCP speeds decrease. You can see the effect in my graph when speeds start off fast and then reduce.

Single Thread Slow Down

This is by design because packets associated with web browsing and gaming do not get de-prioritised.

What is your Thinkbroadband ping monitor like when your single thread slows? Mine stays very good.

Ping during slow single thread

Cheers,

Ian

Thanks very much for the replies guys.

Yeah I was wondering if perhaps the CMTS brand/model had something to do with it, as while it's not country-wide, I know people from various places around the country on VM with the exact same problem. I wonder if there's a way to identify the type of CMTS you're on?

WFQ just seems not so fair when you consider some very traffic-heavy programs/protocols like torrents, Steam, etc completely bypass it by using multiple threads.

If I use a multi-chunk download accelerator it massively improves download speeds for servers that actually allow it, but of course many don't so it's only occasionally an acceptable workaround.

Having spoken to multiple people at VM, a couple have mentioned my 'wire' (whatever they mean by that) is at just over 50% capacity which shouldn't be an issue, but a visiting technician said that 50% is actually pretty high and could be causing problems, but maybe not past the escalation threshold yet.

It's still really irritating that they claim they can't see any problems on the network when they've looked. It makes me wonder what exactly they've been testing, and at what time of day.

WRT my ping monitor, yeah it's mostly fine regardless of single-thread speed: http://www.thinkbroadband.com/ping/share/286f325d1d4...

Thanks!

Edited by deleted (Sat 16-Apr-16 18:10:09)

Having spoken to multiple people at VM, a couple have mentioned my 'wire' (whatever they mean by that) is at just over 50% capacity which shouldn't be an issue, but a visiting technician said that 50% is actually pretty high and could be causing problems, but maybe not past the escalation threshold yet.

I had 95% utilisation value and even then, as it only reached that value for 3 hours per day, it was not classified as a fault. Virginmedia did allow me to leave with virtually no argument though. How bad is the congestion? I was falling anywhere between 1Mbps and 10Mbps every evening.

Virgin also offered a price reduction as an alternative.

Take a look at my TBB tests linked earlier in the thread; they're fairly representative of speeds I'm getting with normal downloads, now generally around 8-15Mbps at peak times.

I've no idea what that ~50% figure is relating to, whether it's peak, 95th percentile, or what part of the network it's from, or even if it's accurate. I have been told by someone else however that VM have very rigid utilisation metrics and even if it's bordering on unacceptable, they won't open a ticket until it consistently crosses it.

Unfortunately VM are refusing to even acknowledge a problem exists in my case. After many months of complaining on the forums (since January, but the problem existed for some time before that) someone finally escalated it to networks and I was given a fault code, but they're still saying they can't find a problem, despite the fact it happens very consistently at peak times and I've exhausted fault-finding options on my end. Even friends in my area are having the exact same problem occurring at the same time.

There's quite a long story of trying to get it sorted, including having technicians out only for them to run speedtest.net to a Virgin-owned server and write down the results of that, and say there's nothing wrong on the RF side so they're not able to do anything. I understand that, but saying download speeds are OK on their reports isn't exactly helping matters. But I won't go over the whole thing again here, suffice to say I've tried everything I can think of to rule out local problems and trying to contact VM via everything from phone to chat to their forums.

I'm thoroughly disappointed with their tech support on this issue to say the least, and that's not even including the weeks I spent of having overseas phone support telling me to try again in a week or to reboot my modem because they've sent some signals to fix my modem...

Really I'm just fed up with it now, sick of getting told there's nothing wrong, and having wasted so many hours of my days off trying to get it resolved and waiting in for needless tech visits.

Thanks!

Edited by deleted (Sat 16-Apr-16 23:50:37)

yeah and here.

https://community.virginmedia.com/t5/Speed/Very-poor...

ouch, wonder if ignition can reveal here.

Yeah that's the thread I started on VM's forums, you can see how much success myself and the other posters with the same problem have had...