[RPNet-user]

This issue started within the last week or so; before that all was ok.
No software has been installed, removed, or edited including for JD2, my ISP is same(no changes)(no firewalls and no AV installed), I download at two locations: location-a(my home); location-b(my brothers) we both have the same ISP and same plan(location-a is still working properly).
The issue happens weather I'm using premium-UL, RPnet-generated, or RPNet-HDD files.
I use eight connections per download@2-downloads:
Issue: Speed starts normal@8-connections then at around 88-92%, the connections drop to one-connection and speed drops from 3MBs to 65KB/s unless I stop and re-start which then the single connection maintains@around 500+ KB/s till it finishes properly speed-wise.
I tested the same files with IDM@8-connections and IDM maintains the speed till the end so I temporarily switched to IDM till i can find a solution.
I updated JD2 to latest with no result so I'm considering of reverting to an older archived version by deleting the entire directory first.
If someone can suggest or recommend a solution or fix that I can try, please advise.

Thanks in advance.

[Jiaz]

JDownloader doesn't have dynamic chunking, that means a download will be split into x parts and once a part is finished, no new part/connection will be opened. That means at the beginning it starts with 8 connections and the more the file comes to the end, the more connections finishes and then it heavily depends on OS/network/ISP/bandwidth... if the other/still running connectoins become faster or stay slow. What you describe happens when *something* (most often ISP) throttle/limit the speed per single connection. That would explain high speed with many connections and slow speed with less connections. When this wasn't the case before, then either your ISP has started to throttle/limit either all connections/or only specific ones or something else on your Setup/System causes this issues. There have been no changes to JDownloader.

What speed do you get with http://cdn8.appwork.org/speed.zip with
1 connection, then 2, 3 and 4...in case 2 is twice as fast as 1, 3 three times as fast as one and so on, then this is a sign for connection throttling/limiting

[RPNet-user]

ISP has nothing to do with it.
Two clients tested were IDM and torrents, both at max consistent speed capacity.
Here are the results, after each result i reset and checked online status otherwise, results were drastically inconsistent:

1@430 KB/s
2@890 KB/s
3@1.2 MB/s
4@1.6 MB/s
5@1.6 MB/s
6@2.1 MB/s
7@2.0 MB/s
8@2.8 MB/s

Forgot to mention that the key is in stopping and restarting after each connection drop.
I just tested a file@8-connections running@2.00MB/s then at around 72% dropped to 3-connections for around 300KB/s, then i stopped and restarted for a steady speed of around 1.0MB/s till she dropped to 1-connection@75KB/s, so i stopped and restarted and she stayed@500KB/s till it completed.

[Jiaz]

Number of connections clearly scales with speed and that is a sign that single connections are limited/throttled.
A single connection should be able to reach 2.8Mbyte/s and not 8 required ones. Also you can't compare http downloads with torrents as they work completely different.

From the given numbers it looks like either ISP/setup/system causes traffic shaping/limiting/throttling.

You say ISP has nothing to do with it. I say ISP may have to do with this as it has happened before all over the world (even here in germany ISPs have throttled single tcp connections) and still happens.

If you want we can do some checks together via Teamviewer, just contact us via support@jdownloader.org

[RPNet-user]

ok, just submitted the email.
Now both locations are showing slow-speeds using the speed test file. Using netlimiter at both locations to monitor each process-connection@8 it would download 6 at about 550kb/s each and two connections well below 100kb/s so when the file reached 80% and the connections dropped to two, it dropped all six of the faster connections leaving the two slowest ones till there is only one connection. The only way around is to stop and continue the download so then both or single connection continue and complete the file at around 550kb/s.

[Jiaz]

Do you have access to vpn/proxy? that way you could check if ISP is throttling/limiting single connections, because it looks like that is what is happening, or just bad/overloaded routes/routing

[RPNet-user]

Originally Posted by Jiaz

Do you have access to vpn/proxy? that way you could check if ISP is throttling/limiting single connections, because it looks like that is what is happening, or just bad/overloaded routes/routing

no i do not, but i will set it up later and test.
i emailed you teamviewer id and pw

[RPNet-user]

yea it appears like my ISP has been making some changes lately...again...and making a mess of our service, i will contact them and do some testing with them.

[Jiaz]

Thanks for teamviewer session. Good luck !