Fixing qBittorrent in Docker, swallowing RAM and locking up the host

IntroI&rsquo;ve had qBittorrent running happily in Docker for over a year now, using the linuxserver/qbittorrent image. I run the docker container and others on an Ubuntu Server host. Recently, the host regularly becomes unresponsive. SSH doesn&rsquo;t work, and the only way to recover is to power cycle the server (running on a small NUC). The symptoms were: RAM usage would climb and climb, the…