qBittorrent official forums

Hi,

I have noticed that a large torrent I am downloading keeps on stalling. It will be chugging along and the speed will then drop to zero. It will either show the green box with arrows or the grey box (not 100% sure of the type of grey box tho), I dont know if the status box changes from green to grey after some time. When the torrent stalls I can see I am still connected to seeds + peers. If I right click on the torrent and resume it, it start downloading again (even if the status box is green). Performance and cache statistics all show 0. I have changed a few things with my setup (New ISP (adsl to 4g), now routing through a vpn and qbt now runs as a different user), though I havent experienced this issue with transmission on the same machine + setup (I will also test another large torrent with qbt tonight).

I have compiled qbt + libtorrent with the --enable-debug flag and have seen the following error in journalctl around when the torrent stalls:
Googling that doesnt give me any meaningful results.
My setup: Ubuntu 16.04 x64 w/8gb ram, qbittorrent-nox 3.3.12, libtorrent 1.0. Hard drives have plenty of free space and are 7200rpm models and permissions on the files are set to rwx for everyone.

Anyone have any suggestions of how to fix the torrent stalling?

Thanks for reading

What DL/UL speeds are you reaching at best? (because high speeds and/or crazy settings in qBT can trigger bugs in qBT, OS, or networking.)

32bit version of qBT?
If so, what's the cache settings?

If you're using 4g wireless internet, it may need more conservative settings even than ADSL despite possibly being faster for network stability reasons.

Hi,

The 4g is capped at 10/1 megabits/s and I qbtorrent was capped at 1000/50 kilobytes/s (same setting pose no issue for deluge or transmission). I'm guessing it was a x64 install as it is x64 ubuntu. Sorry I cant provide cache info as I have switched to another client - I have a 2 week cooling off period with this 4g contract so I need to punish the setup to test it out.

With 10/1 DL/UL mbit/sec speeds and considering the connection type, I'd recommend limiting global max connections to 100 or less in whatever BitTorrent client you use and also lower half open connections to 10 or less.