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Uploading something dramatically affects download

beldar
Hooked
Posts: 5
Registered: 14-01-2017

Uploading something dramatically affects download

Hi there,

 

I've noticed a problem with my bandwidth, when I upload something for example synchronizing my photos with Google Photos, my download speed drops dramatically to more than half of what it normally is.

 

I normally get a stable download of 13Mbps and 1Mbps upload, when I sync my photos my download speed drops from 1Mbps to 3Mbps.

 

Is this normal behaviour? Or is there a problem with my line?

 

Thanks

15 REPLIES
JayG
Aspiring Pro
Posts: 875
Thanks: 47
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Registered: 30-10-2011

Re: Uploading something dramatically affects download

If you are saturating your upload, the download speed will temporarily suffer - the upload and download processes are not quite as independent as their names suggest.

beldar
Hooked
Posts: 5
Registered: 14-01-2017

Re: Uploading something dramatically affects download

Hi,

 

But my understanding was that the upload was capped, therefore if I have a 1Mbps upload the download should drop 1Mbps tops, but it drops almost 11Mpbs...

Community Veteran
Posts: 4,918
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Registered: 10-06-2010

Re: Uploading something dramatically affects download

It's nothing to do with subtracting the upload bandwidth from the download bandwidth, it doesn't work like that.

It's a fairly common problem known as bufferbloat, some routers are worse at it than others, the Plusnet Hub Zero appears to be especially bad at it.

To download, you need to constantly upload small acknowledgements which confirm you've received a piece of the file. The bufferbloat problem when you upload is that a large queue of traffic builds up in the router, and if each acknowledgement simply joins the end of the upload queue, it is delayed until all the other data in front of it gets uploaded.

beldar
Hooked
Posts: 5
Registered: 14-01-2017

Re: Uploading something dramatically affects download

So is there any way to fix or improve the situation? Any config or setting I can flip to increase the queue or something like that?

 

Or is there nothing I can do?

JayG
Aspiring Pro
Posts: 875
Thanks: 47
Fixes: 1
Registered: 30-10-2011

Re: Uploading something dramatically affects download

I believe you can set a limit on the upload bandwidth with Google Drive, but I'm not sure that feature is available with Google Photos.

beldar
Hooked
Posts: 5
Registered: 14-01-2017

Re: Uploading something dramatically affects download

Just found this https://productforums.google.com/forum/#!topic/photos/7OWJbDWPVjY apparently its a more common problem than I thought and Google Photos does not have a upload speed limit setting, so I guess I will be syncing my photos at night from now on.... 

jrilton
Rising Star
Posts: 112
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Registered: 21-07-2014

Re: Uploading something dramatically affects download

I have this problem too, if I take a photo when connected to my wifi network it basically kills my connection. Its only while its actually uploading and only if I take a photo at home so most of the time I don't even notice the problem as I have it set to sync over wifi and mobile date.

DS
Pro
Posts: 563
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Registered: 06-01-2017

Re: Uploading something dramatically affects download

If any of you are seeing this upload problem and you're using a Hub One, it's a known issue and it's currently being looked into back PN.

(it's on another forum topic that Bob Pullen is involved in)

 

edit. This appears to be when PN starting asking us some questions.

beldar
Hooked
Posts: 5
Registered: 14-01-2017

Re: Uploading something dramatically affects download

@DS can you provide a link to that forum topic so I can track it? Thanks

Browni
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Registered: 02-03-2016

Re: Uploading something dramatically affects download

The issue with the Hub One that's being investigated is that the connection gets dropped when uploading, not a slowdown which is happening here.
I must have been really bad in a previous life. This is my 3rd ISP in a row that uses lithium.
DS
Pro
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Registered: 06-01-2017

Re: Uploading something dramatically affects download

You should have received an email regarding the edit above

 

(also, sorry for the typo above - "back" should have been "by")Embarrassed

(edit #2 - oh boy, and another typo, really sorry for all of those email alerts)Cry

Browni
Seasoned Champion
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Registered: 02-03-2016

Re: Uploading something dramatically affects download


DS wrote:

You should have received an email regarding the edit above

 

That's a known bug!

Have a look here for more info.

I must have been really bad in a previous life. This is my 3rd ISP in a row that uses lithium.
DS
Pro
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Registered: 06-01-2017

Re: Uploading something dramatically affects download

@Browni I only mentioned the other thread because Bob wrote "Can anybody suffering from PPP drops caused by large file uploads/saturation please supply the following info?" and uploading plus saturation has been mentioned in this thread.

 

Although beldar reports only seeing a drop in their d/l, it might turn out to be related, then again maybe not....

 

 

Regarding the bug, I'll take a look in a mo for this simple reason - since signing up to these forums my email notification alert tone makes a sound like there's two emails incoming ('pings' in rapid succession) when there's only one!!!!

JayG
Aspiring Pro
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Registered: 30-10-2011

Re: Uploading something dramatically affects download

The OP has an ADSL connection - the disconnection on upload issue is completely different and only affects those with a 40/2 FTTC service.