Speed test starts slow then ramps up

[#1]

Had my ADSL a few weeks now, speed varies from ok (7-9mb) to rubbish (e.g. <1mb) depending on when you test it. One thing I have noticed is that whenever I run a speed test it starts very slow and then shoots up after about 5 seconds to eventually give a decent-ish result. I didn't get this phenomenon on my previous Sky connection, nor do I see it at friends houses so it makes me wonder what's different about Plusnet. In the real world it means that downloads are ok but browsing (i.e. just loading a single web page) is painfully slow to the point where I will cancel it if it doesn't improve.

Have tried contacting the award winning customer services team (who are indeed good when you can get hold of them) but 30 minutes queue on the online chat and up to an hour on the phone is just ridiculous.

[#2]

Hi @Magog66 - Welcome to the Forum.

This is due to the way the TCP Protocol works when this happens the maximum size of frame buffer is being determined. Once this has been established then the test settles down. It's a bit like running a shower, start off slowly till it runs warm the turn up the pressure.

[#3]

Thanks for the speedy response ...

It surely shouldn't take around 5 seconds to determine the frame size buffer? 

Didn't get this with Sky (or BT before that come to think of it) and they all use TCP ... maybe it's a router issue?

[#4]

Well that would be determined by how big your connection was and what was doing the testing. Yes they all use TCP so any speed test site will do the same, it will be down to your bandwidth and the software that's actually doing the test. Try another site and it too will start slow.

Even copying a file across a network does this. It's just the way TCP works. However if there are network issues this may well be more noticeable.

[#5]

Connection is the same size as before, always used Ookla on computer and iPad, so no change there either.

Regardless, bottom line is that numbers are good but real world performance is poor.

[#6]

I've noticed this recently as well. Download speed is fine, it's connecting to websites is taking ages now and quite often the website will fail to load and when you retry it then works. It's a bloody joke.