Homelab, Linux, JS & ABAP (~˘▾˘)~
 

[Docker] Portainer → Dockhand

I have been using Portainer for about 6 or 7 years. Recently the company announced version 3.0, a rebuild of the platform around Kubernetes, and that there will be no community version of it. Although version 2 will still get fixes and backports when possible, I took the opportunity to try something new. Especially since I’m not interested in Kubernetes and this seems to be the focus of Portainer from now on. For quite some time I already had Dockhand in my bookmarks, but never took a close look. I launched a container and have to say, the user experience is similar to Portainer’s, it even feels a bit cleaner and has a few more features. The setup just took a few minutes and everything was working out of the box. Great!

services:
  dockhand:
    image: fnsys/dockhand:v1.0.54
    container_name: dockhand
    restart: unless-stopped
    environment:
      - DATA_DIR=/opt/dockhand
    volumes:
      - /opt/containers/dockhand/data:/opt/dockhand
      - /var/run/docker.sock:/var/run/docker.sock
      - /opt/containers:/opt/containers           # this path is added to access local docker-compose.yml files, created outside dockhand
    group_add:
      - "988"
    networks:
      - proxy

networks:
  proxy:
    external: true

[Firefox] Freezes computer

For the past few weeks, my computer was randomly freezing for about 30 seconds. After a quick search, it became clear that it was a memory issue, even though my computer has over 32 GB of RAM…

> journalctl -k -b -o short-precise

Sep 23 09:39:38.873173 myPC systemd-journald: Under memory pressure, flushing caches.
Sep 23 09:39:41.632171 myPC systemd-journald: Under memory pressure, flushing caches.
Sep 23 09:39:44.072486 myPC systemd-journald: Under memory pressure, flushing caches.
Sep 23 09:39:50.630124 myPC systemd-journald: Under memory pressure, flushing caches.
Sep 23 09:40:18.142581 myPC kernel: upowerd invoked oom-killer: gfp_mask=0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), order=0, oom_score_adj=0

> journalctl -k -b --since "2026-09-23 09:39:30" --until "2026-09-23 09:41:30" \
  | grep -iE 'oom|killed process|kill process|out of memory|memory cgroup'

Sep 23 09:40:18 myPC kernel: oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/user.slice/user-1000.slice/session-c2.scope,task=Isolated Web Co,pid=2666576,uid=1000
Sep 23 09:40:18 myPC kernel: Out of memory: Killed process 2666576 (Isolated Web Co) total-vm:10469216kB, anon-rss:7162184kB, file-rss:196kB, shmem-rss:1752kB, UID:1000 pgtables:54092kB oom_score_adj:200

As it turned out, the problem was caused by Firefox (Killed process Isolated Web Co). Fortunately, the solution was quite simple. I enabled the unloadOnLowMemory setting:

about:config → browser.tabs.unloadOnLowMemory →true

Since then, everything is running normal again. I also tried to identify a specific extension or website, which needed too much memory via

about:processes

about:memory

but it was nothing out of the ordinary. I guess I just had too many Firefox windows and tabs open…