Throttling Experiment

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Hogrod

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This post may be opening something that was looked at before, but I could not find it so here is something that I found interesting.

I happened to be doing some end of month downloading (unbelievably on an I-go package) since I'd not used the Internet this month.

I noticed that every download I had made this week from mostly international sites had been limited to a stable 30 to 40 KB/sec speed.

If i had 3 downloads on the go each would be again around 30 to 40 KB/sec. I thought this was rather coincidental or a just a fluke.

I then took a look at the Iburst interface to see what link speed my connection was running at.

I found the following pattern:

1 download 40KB/sec = 250 kpbs link speed
2 simultaneous downloads each at 30KB/sec = 550kpbs link speed
3 simultaneous downloads each at 30KB/sec = 750kbps link speed
(approx figures)

Basically I was watching the link speed go up every time I added a new download.
However, I am certain a few months ago just having one download would make the link speed shoot up to as fast as possible e.g 900-1000kbs.
One example, downloading or streaming a video file from www.break.com would get a good 700 to 900 kpbs link speed. However, today i only get a 250kpbs link speed for a movie clip.
It seems now link speed is being restricted per task or file download in this case.

This brings me to the next finding:
The more you give your broadband to do e.g. multi-file downloading, the faster the link speed will work. Whereas back last year, giving it a single task to do would make the link speed work as hard as possible, and not be contained to say 250kbps per file, as in my example

For conclusion, the only why I can reach the golden 1mbps figure is by doing lots of 'downloading' at once instead of just downloading one thing.
Therefore it appears my link speed is being throttled to a max link speed of 250kpbs per file.

Can anyone explain to me what I've found here, if its something new, it might explain why some people may be wondering why they can never get a link speed of 1mbps when doing a single task.
If you want 1mbps then try downloading 4 things at once, and see what link speeds you get.

And a final teaser for you:

With this throttling does it actually mean the download takes longer to finish than with no throttling?
E.g if a file is downloading at 40KB/sec with a 250kbps link speed, would it finish before or after the same file that was downloading at 40KB/sec with a 1mbps link speed.

Andy
 
andytl5 said:
With this throttling does it actually mean the download takes longer to finish than with no throttling?
E.g if a file is downloading at 40KB/sec with a 250kbps link speed, would it finish before or after the same file that was downloading at 40KB/sec with a 1mbps link speed.

Andy
Click to expand...
I think you have answered your own question here:
If a is downloading at 40KB/s and b is downloading at 40KB/s: in one second a will have downloaded 40KB, and b would have downloaded :eek: 40KB. Hence the speed is Forty Kilobytes per second.
 
andytl5 said:
Can anyone explain to me what I've found here, if its something new, it might explain why some people may be wondering why they can never get a link speed of 1mbps when doing a single task.
If you want 1mbps then try downloading 4 things at once, and see what link speeds you get.
Click to expand...

What you describe is similar to my experience with single threaded downloads. I can get a file locally at 70-80KB/s, but an international will only come in at 40-60KB/s. But if I use a multi-threaded download manager, any file whether local or international will come in at >100KB/s (unless the source server restricts the number of simultaneous connections.)

The answer to your question is get a multi-threaded download manager like Flashget or Net Transport and enjoy receiving your downloads at full speed.
 
I believe the above is correct, I use IDM (internet download manager) and it open 8 conncurrent connections which speeds things up ALOT.

What I would like to know is how this effects browsing. Are you browsing with a single threaded effect (speed) or does the fact that you set up pipelining or more than 8 or so connections to a server make browsing seem "multi-threaded"? Either way I'm shure that when downloading a single large picture, like from a pic search, then it only seems to get the effect of a single threaded download. However I seem to remember getting up to 700kb showing up on DUMeter when loading a single picture on its own in my browser. Lately I think this has also decreased, making browsing seem slower than on ADSL alot of the time.

And a 40kb file transfer is going at 40kb. It means that this is the speed of your line or your download is being restricted. In any case it will finish at the same time. Except that on Iburst the speed flactuates, so a 256kb link might not always be capable of full 40kb speed, whereas 1mb should be able to keep more consistently at 40kb.
 
Further to mine and your points,

If anyone therefore complains that they are experience low link speeds, would it be safe to advise them that there is in fact nothing wrong with their connection. They can get the full 1mpbs if they actually use the broadband connection to do a broad number of task.

I guess you would by what I've seen never get 1mbps link speed for loading a web page, you'll only get it doing multiple things at once.

Is it that the problems lie in how fast the data is coming from some server in the US to the Iburst servers? Is this where the bottleneck is?

I do see a lot of posts about how fast their link speeds. I think the Telkom line speed test might be misleading since it does not employ the use of multi-downloading to judge how fast your connection is when people start talking in kbps speeds and why they can't get 1mbps.

I guess I must remember that the Iburst interface on your desktop only shows link speed between you and the tower you are connected to. It does not show (in my limited understanding of terms) how fast it is between a server somewhere with the file and the Iburst servers and towers.

Do we really know what the true speeds are, how do we tell? From what I've heard and said, is the only guarantee we buy into from Iburst is the possibility of getting a 1mbps connection between my computer and that huge tower down the road. And in fact there is no guarantee about how fast that connection is between the server in the US and Iburst's servers, since this is out of Iburst's control. ...What does 1mpbs connection really mean.

Andy

(uh-oh 0.06mb left)
 
sorry for kinda hijacking the thread, but i thought i would let you know of a free download manager called... [drum roll]... Free Download Manager!

if is opensource and works really well with lotsa features: bandwidth limiting, scheduled downloads, browser integration, website spider, download groups (by file type), zip preview and many more.

Version 2 has just been released and the download is only 1.5Mb.

support open source and give it a try.
 
Browsing is by it's nature multi-threaded. Your browser sends multiple requests for the multiple elements on your page.
 
arf9999 said:
Browsing is by it's nature multi-threaded. Your browser sends multiple requests for the multiple elements on your page.
Click to expand...
your browser pipelines the requests (one connection, multiple requests). it can however open multiple connections to the site.
 
Not all browser pipeline by default, Firefox doesnt even you have to enable it. But all browsers open multiple connections to sites so thats probably wy browsing does go up to arounf 600-700kb for me.

However if Iburst was like ADSL where you can get your full speed on a single threaded download (multi-threading helps a bit) then Im shure our experience would be alot better. Not everyone always wants to have to browse three sites and downlaod something just to get 1mb, becuase what they experience on the net is more like 100kb. Usually we just want to visit a site and maby open a link or two at the same time.
 
Ekhaatvensters said:
Not all browser pipeline by default, Firefox doesnt even you have to enable it. But all browsers open multiple connections to sites so thats probably wy browsing does go up to arounf 600-700kb for me.
Click to expand...

How to we setup Firefox and/or IE to enable 'pipelining'?
If you think it will be useful for me to enable then let me know.

Thanks
Andy
 
Just get an extension that does it for you from http://addons.mozilla.org
Fasterfox will do fine and you can set a few other options, but htere are apparently better ones.

To do it manually you type about:config into the browser bar lie you were going to a web site with that adress. Now scroll down to the network section and look for the entry which says enable pipelining change it to true, then set the number of pipeplines underneath it. A setting like 6-8 should be fine.
I dont use FF anymore so i cant remember the exact entry to enable pipelining. "network.http.pipelining.maxrequests" I think thats it though...

But when I used FF I fouind that enabling pipeling with Iburst made some of the pictures on a site not load. There would always be a few pics on any site that just wouldnt load, diabling pipeling fixed this.

I dont know if IE can do this, but use Opera 9 anyway. Much faster and loads all pics fine.
 
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You can customize your firefox by typing about:config in the address bar:

Here is a resource to get you going:

"http://kb.mozillazine.org/Firefox_:_FAQs_:_About:config_Entries"

The section dealing with multiple connection etc is "network".

EDIT: EkhaatVensters beat me to it!

FasterFox: Dynamic speed increases can be obtained with the unique prefetching mechanism, which recycles idle bandwidth by silently loading and caching all of the links on the page you are browsing.

So I reckon FasterFox is not such a good solution for SA where bandwidth needs to be conserved.
 
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Gatecrasher said:
FasterFox: Dynamic speed increases can be obtained with the unique prefetching mechanism, which recycles idle bandwidth by silently loading and caching all of the links on the page you are browsing.

So I reckon FasterFox is not such a good solution for SA where bandwidth needs to be conserved.
Click to expand...

That option is no longer enabled by default. They stopped it a few versions ago. You can enable it only if you have uncapped access or really want to.

They must have relised its not a very good idea.

But anyway, after customizing my FF for about a year and enabling every speed enhancement i could find, it ended up that Opera was simply faster by just chaning the usual settings in the program, only two actually need to be changed for performance.
My Firefix slowed down tremendously over time, so Im sticking to Opera now, with IE7 beta as my backup and to use for those Microsoft apps that insist on opening IE instead of your default browser.
 
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