[BUG] Memory usage going up when downloading, stays high even when download finished

[mrtomtech]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

When I download something, my memory gets filled up and never goes down unless I restart the container.
I did manage to fix it by applying these settings in the advanced section but I expect this to not happen in the first place.

Expected Behavior

No response

Steps To Reproduce

1. Start download in qbit
2. Monitor memory usage and see it going up
3. When download finishes, keep monitoring memory to see it not going down

Environment

- OS: TrueNAS Scale 25.10.1
- How docker service was installed: pre-installed

CPU architecture

x86-64

Docker creation

qbittorrent:
    image: linuxserver/qbittorrent:latest
    container_name: qbittorrent
    network_mode: service:wireguard
    environment:
      - PUID=568
      - PGID=568
      - TZ=Europe/Amsterdam
      - WEBUI_PORT=8082
      - TORRENTING_PORT=45448
    volumes:
      - /mnt/apps/configs/qbittorrent:/config
      - /mnt/tank/media:/media
    depends_on:
      wireguard:
        condition: service_healthy
    restart: unless-stopped

Container logs

root@tomtechnas[/mnt/apps/home/tom]# docker logs qbittorrent
[migrations] started
[migrations] no migrations found
───────────────────────────────────────

      ██╗     ███████╗██╗ ██████╗
      ██║     ██╔════╝██║██╔═══██╗
      ██║     ███████╗██║██║   ██║
      ██║     ╚════██║██║██║   ██║
      ███████╗███████║██║╚██████╔╝
      ╚══════╝╚══════╝╚═╝ ╚═════╝

   Brought to you by linuxserver.io
───────────────────────────────────────

To support LSIO projects visit:
https://www.linuxserver.io/donate/

───────────────────────────────────────
GID/UID
───────────────────────────────────────

User UID:    568
User GID:    568
───────────────────────────────────────
Linuxserver.io version: 5.1.4-r1-ls433
Build-date: 2025-12-28T07:02:08+00:00
───────────────────────────────────────
    
[custom-init] No custom files found, skipping...
WebUI will be started shortly after internal preparations. Please wait...

******** Information ********
To control qBittorrent, access the WebUI at: http://localhost:8082
Connection to localhost (127.0.0.1) 8082 port [tcp/*] succeeded!
[ls.io-init] done.
root@tomtechnas[/mnt/apps/home/tom]#

[github-actions]

Thanks for opening your first issue here! Be sure to follow the relevant issue templates, or risk having this issue marked as invalid.

[j0nnymoe]

This is less a container problem but more specific to qbittorrent itself. You're likely experiencing a bug in libtorrentv2 with your specific environment.

I would suggest trying the libtorrentv1 tag we also offer and tinker with what settings you have.