Download speed starts fine but after about 20-30 s drops to a few Bps.

[mgillard1976]

If I uninstall QBT and reinstall it goes back to normal with good steady DL speeds. After a couple days the same thing happens again.

I've tried:

• Rebooting the router
• Changing ports
• VPN and no VPN

The only thing that works is to uninstall and reinstall. Then I'm good for a day or two.

Windows 10 64 bit
QB version 4.1.6

[Switeck]

In those "couple days", are you downloading like 10+ torrents and/or over 10 GB of torrents?
If so, you could be stumbling across qBitTorrent's problems with torrent queuing or upload slot handling or even upload speed overloads (which can cause exponential download speed die-offs).

[mgillard1976]

[quote="Switeck"]
In those "couple days", are you downloading like 10+ torrents and/or over 10 GB of torrents?
If so, you could be stumbling across qBitTorrent's problems with torrent queuing or upload slot handling or even upload speed overloads (which can cause exponential download speed die-offs).
[/quote]

I have less than 10 torrents seeding. It's possible I went over 10 at some point but the last time it was definitely less. I'll search through the forums using those keywords though. Is there a solution if one of those is actually what's happening?

[Switeck]

With so few torrents, disable torrent queueing (that's how it's misspelled in qBT!) and manually start+stop torrents as desired.

Uploading too quickly can cause massive packet loss and when that happens download speeds can suffer immensely.
An upload speed limit that takes into account overheads and changing conditions may mostly or completely prevent that.

Also, with really bad networking hardware/software, busy torrents could cause slowdowns or crashes.
Motherboard drivers for NIC cards even can be a cause -- they can have a built-in software firewall that after some extended period of time goes into a "learning mode" and starts considering BitTorrent traffic hostile and slow and blocking it...or just be buggy under heavy loads and require reboots to halfway restore them.

And lastly, many antivirus/antimalware products now have software firewalls...and they should've stuck with just rooting out malware instead of thinking they could do networking well too...because they suck at it!

[mgillard1976]

[quote="Switeck"]
With so few torrents, disable torrent queueing (that's how it's misspelled in qBT!) and manually start+stop torrents as desired.

Uploading too quickly can cause massive packet loss and when that happens download speeds can suffer immensely.
An upload speed limit that takes into account overheads and changing conditions may mostly or completely prevent that.

Also, with really bad networking hardware/software, busy torrents could cause slowdowns or crashes.
Motherboard drivers for NIC cards even can be a cause -- they can have a built-in software firewall that after some extended period of time goes into a "learning mode" and starts considering BitTorrent traffic hostile and slow and blocking it...or just be buggy under heavy loads and require reboots to halfway restore them.

And lastly, many antivirus/antimalware products now have software firewalls...and they should've stuck with just rooting out malware instead of thinking they could do networking well too...because they suck at it!
[/quote]

So I reined in my upload speed, turned off torrent queueing. I turned off my AV temporarily to check and the problem returned. I'm starting to think that it's the motherboard driver (killer something or other) that is causing the issue. I've downloaded a new driver that is supposed to be free of this component but I believe I still need to remove the "killer". I'll try the new driver and report back.

[Switeck]

Other posts elsewhere suggest it's garbage:

https://www.reddit.com/r/qBittorrent/co ... bs_on_lan/
"Was able to find the reason for this.  It was the Killer Networking Service that was capping it.  Disabled it and now there are no more issues."

https://linustechtips.com/main/topic/82 ... ble-speed/
"Okay guys problem solved. I clicked on "update download speed" on the Killer Network driver and my speeds are awesome now. 16mb/s which I have never achieved before with Wi-Fi!"

https://forum.tixati.com/support/2844/
"it wasn't Tixati's fault. I run a mainboard that uses a Killer Networking Ethernet chipset. It turns out there was a bug in the drivers that was causing severe memory bloat when lots of data was being pushed through the NIC"

[mgillard1976]

So I can't actually find a killer driver. It doesn't seem to be installed so I'm thinking that's not the issue. I may try using another client to make sure it's not related to QB.

I do have an orange upload arrow which I assume is a problem. I have the port forwarded correctly in my router because I've checked it using canyouseeme.org

Could that be related??

[Switeck]

Yes, if the router is correctly forwarded then something on your computer is blocking qBitTorrent...and possibly only qBitTorrent!

[mgillard1976]

Is there a good way to track this down? Log files? Could it be the ISP?

[Switeck]

You have to know what AV and firewall software is on your computer and test with them uninstalled.

Log files of qBT are only slightly helpful under best of circumstances for this, since the problem isn't qBT.

Possible, but if it worked before...and recently...doubtful.

[mgillard1976]

I've turned off my AV and as far as I know there is no firewall installed. I'll keep posting back with progress. I might not be the only one with the problem.

[Switeck]

Once the problem starts again, does starting a new torrent (like a known-to-be-crazy-fast Linux distro torrent) also immediately run slow?

[mgillard1976]

I've turned off the windows firewalls and the problem hasn't returned yet although I still have the orange upload arrow. If the problem returns I'll try the linux distro and report back.

[mgillard1976]

The download issue hasn't returned after turning off the windows firewalls. However I still an orange upload arrow. This is probably not related so if I can't find a solution on my own I'll post a new thread.

[carsten]

I got the same issue. Turned off windows firewall, but no change. Starts downloading with like 400mb/sec and drops to 0 within a minute. Then click the play button again and again downloads and dies within a minute.

I recently had a windows update, and recently installed the update fro QB, so not sure whats going on. But for now, I can't use this at all.

And I got so much to share...