Progressively slower online backup to Mozy - anyone got any ideas?

[#1]

Just wondering if anyone has any ideas what is going on with my line.
I have an unlimited fibre connection. For the past few days I've been setting up a cloud backup solution for my machines using Mozy who I've used for years. Anyway, I added a machine to my backup set a few days ago and it sent 40GB of data to Mozy. I don't have any speed graphs but I do have my broadband ping at the time:

As you can see I was caning the line overnight for about 12 hours with a consistent 1MB/sec upload speed. which I guess is where the latency comes from. All good so far.
I've added another machine and have a completely different graph. Although this backup started at 1MB/sec it's just got slower and slower until now I'm getting 11KB/sec:

You can see the tail-off on the ping graph. Then at 12:55 my line lost sync altogether and took about 5 minutes to reconnect.
Now all the speed tests I've run say I've still got an 11Mb/sec upload speed. I just can't get it any more talking to Mozy.
So, do Plusnet have some sort of throttling going on that I may have triggered?

[#2]

Hi there,
Not on upload, no - we can't actually throttle it since by the time it hits our network it's already been through the connection's bottleneck (the route from the exchange to your premises). I have asked Dave to have a look for you, but it's certainly nothing deliberate being done on our part.

[#3]

Thanks. It's very strange. Here's the same information from my router. A definitely gradual drop-off in throughput which ended at the loss of sync.

[#4]

Loss of sync would hint at an issue with the cabinet, as that's where the signal is generated, or the modem, which is where it terminates Not sure why it slowed down like that over such a long period of time though. But given what you've just said, it does sound more like a line fault.

[#5]

Hmm. It is odd. Are you still able to post a graph of my resyncs as I'm a fibre user? Strictly there shouldn't be any at all over the past month.

[#6]

Here's a graph showing your connections to us - the marks aren't necessarily resyncs but they do show where your connection to us was lost and then regained, hope that helps?
<img src="http://community.plus.net/visualradius/generated/image13766584678553.png"/>

[#7]

Hi,
Matt asked me to have a look at what was going on, unfortunately I don't have enough data to be 100% certain what the problem was but based on what I can see I can make an educated guess.
Looking at your graph you can see the upload running along at a nice rate for a few hours and then it drops like a stone but there's a curve to the decrease, it doesn't die, it keeps going just slower and slower as time goes on. Then your line resyncs.
What we can see is that before the line resync'd it was sync'd about 50.2 Mbps down and 14.5 Mbps up, but afterwards it decreased to Downstream Speed 48.4 Mbps, Upstream Speed 13.3 Mbps. My thinking is that your line started erroring sometime around the time the speed started to decrease and then gradually got worse before the line finally resync'd at a lower rate at about 1am.
Is it working normally now? You're right about the latency graph, it will show high latency while you max out your upload because the ping is going to be fighting it out with whatever you upload for priority over the upstream speed.

[#8]

Hi Dave
As far as I can see the uploads are working ok at the moment. Is there any test that I can do to discover if I do have a line fault? It seems a pity that I'd drop 2Mb/sec from the line without there being some reason. It would be cool to get to the bottom of what's going on and perhaps get the last couple of Mb back again!

[#9]

Quote from: Matt

Here's a graph showing your connections to us - the marks aren't necessarily resyncs but they do show where your connection to us was lost and then regained, hope that helps? <img src="http://community.plus.net/visualradius/generated/image13766584678553.png"/>

Thanks Matt. It really does look odd. If I'm reading things correctly it's saying that I had 11 days of uptime without issue. Then when I did my first backup I had a resync around 1am. I guess things got going quickly enough for the backup to continue and backup speed was OK throughout.
Anyway, then I had no resyncs for a couple of days until I next did a backup and again I got a resync around 1am, though this time with a tailing off of performance. In fact you can see it on the next day's graph:

The login around 12 on the 15th on your chart was me rebooting my router to see if that would help.
So, is there any kind of fault that only manifests itself when i'm caning the line in upload?

[#10]

I've run a few some checks on your line and there's nothing obvious that has caused this and there's no fault detected.
I'd suggest monitoring your line and you can always try a power cycle(better in daylight hours) to see if there's an improvement.