cancel
Showing results for 
Search instead for 
Did you mean: 

High latency?

EnglishMohican
Rising Star
Posts: 297
Thanks: 28
Fixes: 1
Registered: 08-04-2009

High latency?

My Broadband Ping - PostProblem Webpages are loading very slowly, sometimes 20 seconds until anything appears. Any site can be slow including BBC and Google. I know it is Black Saturday but this is intermittent, sometimes slow and sometimes quick but slow getting more and more frequent so hard to know when it started but perhaps a month or more ago - so its not just shopping. Is the attached graph one of Plusnet's known problems, is it just Plusnet or is everybody seeing it - or is it just me?
7 REPLIES
Community Veteran
Posts: 4,916
Thanks: 335
Fixes: 16
Registered: 10-06-2010

Re: High latency?

I don't think that graph shows any particular problem, it looks probably about as good as it gets for a slower connection.

EnglishMohican
Rising Star
Posts: 297
Thanks: 28
Fixes: 1
Registered: 08-04-2009

Re: High latency?

I have checked these graphs every so often over my years with Plusnet. This is far worse than I am used to seeing. I agree that I have no firm link between the high latency and the slow webpage loading but surely it is a reasonable link to make.

So no, I do not agree it is typical. I also see no reason for variation in latency to be linked to absolute line speed

Gel
Pro
Posts: 1,386
Thanks: 133
Fixes: 10
Registered: 02-08-2007

Re: High latency?

EnglishMohican
Rising Star
Posts: 297
Thanks: 28
Fixes: 1
Registered: 08-04-2009

Re: High latency?

Thanks for the idea but yes, I have OpenDNS and Google DNS set up as well as the Plusnet DNS (in that order of initial preference). They all feed into a  local DNS caching server that gives 1ms response for the common addresses and as I understand it, monitors external DNS response times so that it chooses the fastest external server at any moment.

I did wonder whether the local server could be the problem but the pages can be slow even when I feed the browser a numerical IP address taken straight off the web.

Community Veteran
Posts: 4,916
Thanks: 335
Fixes: 16
Registered: 10-06-2010

Re: High latency?


EnglishMohican wrote:

I also see no reason for variation in latency to be linked to absolute line speed


Obviously, if you have more bandwidth, your connection will be at maximum utilisation for less time while loading webpages. And while your connection is maxed out, things will have to wait (unless they can jump the queue with some sort of traffic management / prioritisation), so latency will be higher during that time.

Are you on the new network? There appears to be little or no traffic prioritisation on the new network. On the old network, ping replies and dns answers got given a higher priority. Whereas on the new network, or at least on the part of it that I'm on, they aren't.

EnglishMohican
Rising Star
Posts: 297
Thanks: 28
Fixes: 1
Registered: 08-04-2009

Re: High latency?

How do I tell whether I am on the new network? Traceroute to bbc.co.uk follows in case that helps.

1 ***local router ******* 46.835 ms 46.798 ms 46.751 ms
2 lo0.central10.pcn-bng02.plus.net (195.166.130.249) 29.437 ms 31.148 ms 29.734 ms
3 411.be6.pcn-ir02.plus.net (84.93.253.79) 33.446 ms 35.020 ms 33.556 ms
4 195.99.125.140 (195.99.125.140) 38.753 ms 195.99.125.144 (195.99.125.144) 39.079 ms 40.868 ms
5 peer1-et-1-1-0.redbus.ukcore.bt.net (62.172.103.45) 41.335 ms peer2-et-1-3-0.telehouse.ukcore.bt.net (195.99.127.23) 42.661 ms 62.172.103.13 (62.172.103.13) 43.802 ms
6 * * *
7 * * *

I accept that a link running at high load could struggle to find a slot for a message to go in but my line is not used for streaming (maybe occasionally) or other demanding operations. There might be two of us reading webpages and maybe a phone checking a mail server but none of this should max out my line or get anywhere near. The graph at the top of the thread would have required me to be stressing the line hard for 3 hours solidly. It does not happen.

Community Veteran
Posts: 4,916
Thanks: 335
Fixes: 16
Registered: 10-06-2010

Re: High latency?

Your graph looks to me like it's affected by short bursts of activity, which could be loading all the images and other content on a webpage. The only way this wouldn't briefly use the line to full capacity would be if all the images etc. loaded almost instantly, before the TCP protocol scaled up the buffer sizes. It's only the yellow maximum latency that is significantly increased on your graph, which might be only one ping packet in the minute, with the average latency only affected very slightly.

Actual streaming would not necessarily use the full bandwidth of the connection, after a small buffer builds up, the audio and video data can then be sent at the bitrate of the media rather than the full bandwidth of the connection.

Which 3 solid hours on the graph are you thinking of?

Also, what is your line speed?

I'm not even sure from that traceroute whether or not you are on the new network. Perhaps you are but you've got a static IP address and so it's difficult to tell?