Adding new Torrents sometimes causes UI to freeze

[GenericComrade]

I've had a problem with adding some torrents that causes the UI to completely freeze and lockup, even on a fresh install.

The confusing part is that it doesn't always occur. It either takes a few seconds to add (a very large torrent) or the UI completely freezes up, eats 100% CPU and never comes back. This will occur with the same torrent file too. It may be related to changing one of the inner torrent folders, but I am unsure.

I know it's only the UI freezing since later on, since after I got some torrents running, when I added a torrent and the UI froze up, and I can see on my firewall that it was still seeding/leeching perfectly fine.

[GenericComrade]

Windows XP SP3 - qBittorrent v3.0.6

Steps to reproduce:
Add Torrent: Touhou album image collection v.15.torrent
Selected Custom Path: G:\Seed\Temp\
Expanded Additional Settings.
Rename Base Folder from "Touhou lossless music collection" to "Touhou".
Unchecked Start Torrent.
Clicked OK.
qBitTorrent eats 100% CPU and never returns.

I don't know what allows it to add sometimes, but just tested it with a clean install and it freezes. That bug has forced me to recheck my torrents, which took a few hours .

[tekko]

"Pre-allocate disk space for all files" - is this option checked or unchecked?

Since you said it's a big torrent, maybe it's taking the time to allocate the space.

While qbt is freezing, check to see if your antivirus is scanning the files.

[tekko]

I googled and found out that the music torrent is over 1TB and the image torrent is over 37GB... 

[GenericComrade]

The torrent I linked was the smaller torrent so it's easier for people to confirm that it's freezing by trying to add it themselves.

I have pre allocate files off and there's no sign of it preallocating files on my hard drive. I do not use a real time anti virus that is always running.

Did you try adding the torrent I linked to see if it freezes your qBittorrent? After all, I posted the reproduction steps, and you don't even have to start the torrent.

Also if you read my post, sometimes the torrent adds within a few seconds, and sometimes it just freezes the UI. I don't know why.

[ironcross]

Well, i started it - no problem. It downloads, nothing freeze. Pre-allocate is on.

[GenericComrade]

Did you perform all the steps I had listed? Like renaming the base folder within the torrent?

[Avelon]

I can confirm that it consumes a lot of resources - while adding the 23.500 files (pre-allocation and a fragmented disk ) and when exploring through the content. But I can easily rename the folder. Torrents start by default.
I guess it might be related to the language, too. qB shows the correct file and folder names (Japanese, Chineese?), but windows (well, my Windows) doesn't show the correct letters. I guess there's more than 1 file/folder that contains of 5 characters and so Windows needs to rename it since it cannot allow more than 1 file/folder to have the same name (with those 5 characters). So I guess it's not just the 'here I come, clean all your disk-space for me!' torrent that consumes those resources, but also a Windows sub-process dealing with those names. But that's just a guess.
Such a huge torrent (37GB and ~23.000 files) has even more parts. So it's windows and the torrent client that need to prepare for this impact.

I've noticed that during the 'checking torrent' process it lowers all transfers to a minimum (about 5 seconds). So it's a CPU issue, I guess, because my disk cache is set to 128MB.
But I'm also playing a video and running another app.
I put my bet on: CPU

Since ironcross looks like a gamer, I think his CPU is better than yours (GenericComrade) and mine :p

[GenericComrade]

I'm not sure how closely you guys are reading my posts, but I have already explained that there is no pre-allocation going on. Furthermore, even in the original post, the torrent is sometimes successfully added and within a few seconds, and other times it eats 100% CPU and never comes back:

[quote="GenericComrade"]
[...] It either takes a few seconds to add (a very large torrent) or the UI completely freezes up, eats 100% CPU and never comes back. This will occur with the same torrent file too. [...]
[/quote]

[Avelon]

I've read it. Pre-allocation makes things 'worse' in this case, so it's not a bad thing. It asks for more, not less.
I've turned it off. Adds much faster now.

[quote="GenericComrade"]
It may be related to changing one of the inner torrent folders, but I am unsure.
[/quote]

It is not if this behaviour happens occassionally while adding the torrent. Renaming is or should be another spot. But it's not the same problem.

What happens if all other torrents are stopped. Get qB lazy and add it. Get qB busy and add it. Any difference?

[GenericComrade]

I've had it occur with a clean qBittorrent 3.0.6 portable, and that's exactly what my reproduction steps are from.

I've also had it occur with a normal qBittorrent v3.0.6 install, with Terabytes of torrents running, and the UI locks up and eats 100% CPU, but the already running torrents continue seeding/leeching (I can tell from my Firewall).

[GenericComrade]

[quote="Avelon"]It is not if this behaviour happens occassionally while adding the torrent. Renaming is or should be another spot. But it's not the same problem.[/quote]Sorry, but I'm not understanding what ya mean here. I do the folder rename always during the add torrent process, as explained in my reproduction steps.

[tekko]

I am using v3.1.0 alpha. I followed the steps and it's still freezing as I post... High cpu usage and I forgot to backup before I try. 

[GenericComrade]

Hey I warned ya it was freezing me. Sorry . It took me 8 hours one time, to re-check all the torrents I had seeding/leeching :/

Edit: I usually force it closed. I think one time I waited 45 minutes, and it actually 'crashed' and my debugger tried to attach to it 

[tekko]

[quote="GenericComrade"]
Hey I warned ya it was freezing me. Sorry . It took me 8 hours one time, to re-check all the torrents I had seeding/leeching :/
[/quote]

Well, I didn't blame you. I said I forgot. It's freezing still... so it's confirmed by me at least.

P.S. Clarifying that it was an embarrassed face, not an angry face.