DietPi-Software | Plex Media Server: Current versions fills /tmp until it's full

[MichaIng]

Creating a bug report/issue

Required Information

• DietPi version | v6.30
• Distro version | buster
• SBC model | Odroid XU4

Additional Information (if applicable)

• Software title | Plex Media Server
• Was the software title installed freshly or updated/migrated? migrated
• Can this issue be replicated on a fresh installation of DietPi? WIP

Steps to reproduce

1. Install/update to current PMS package
2. Play some video files
3. ls -Al /tmp; du -ms /tmp/*

Expected behaviour

• Temporary files created by PMS should be fair below 1 GiB

Actual behaviour

• Temporary files reach 1 GiB before other things crash due to /tmp tmpfs being full

Extra details

• https://github.com/MichaIng/DietPi/issues/3544#issuecomment-634293391

[MichaIng]

I'm trying to replicate. Need some large video files for this, it seems, music files do not lead to any tmp files from what I can see. Need to copy some things over, WIP 😉.

[MichaIng]

Hmm, I was playing a larger MP4 h.264 video, verified that transcoder is active, two dirs are present in /tmp but nothing gets written to them.

@Doctorbeefy
Which kind of media files did you play or manage with PMS when /tmp gets filled?

[Doctorbeefy]

@MichaIng Mainly mkv I do have some mp4. I have found going to Settings > Library and setting Generate intro video markers to never resolved the issue. They added intro skipping which then scans for intros when you add content. I have a feeling this is what was causing tmp to fill up.

After setting Generate intro video markers to Never I no longer have the issue.

Maybe this will help someone in the future here

[MichaIng]

Interesting, I see the changelog for the version that matches mine: https://forums.plex.tv/t/plex-media-server/30447/345?u=michaing
But I do not see intro detection setting, just automated preview and chapter thumbnail generation. Is it probably a premium feature? Because I have a free account only, for testing 😉.

---

A found it: https://support.plex.tv/articles/skip-content/
Plex pass feature indeed.

If you want to help fixing this upstream, you can re-enable it, until you run into errors or check the following in between:

ls -Al /tmp/* # List content so show which dirs are created by PMS
du -sm /tmp/* # Show size of content in MiB

Then disable the feature, clear /tmp content or restart and do the same. The direct comparison should serve as prove that the new intro detection is the culprit to make their devs have a closer look.

---

Ah ChuckPa also mentions that new intro skip feature reads/write much: https://forums.plex.tv/t/pms-stopped-honoring-temporary-directory-setting-now-uses-tmp/594501/49?u=michaing

---

Related topic: https://forums.plex.tv/t/lots-of-traffic-in-tmp-on-intro-detection/595402?u=michaing
Was closed by Chuck, went too much into discussion, but the other user had the fair point that the current situation is problematic, having a feature enabled by default that writes easily >1 GiB data into /tmp by default which usually is a tmpfs with 512 MiB only by default (on DietPi we increase it actively to 1 GiB, respectively 50% of RAM+swap).

[Doctorbeefy]

@MichaIng I have the 1.4 gig file that plex created if that would help. I am unsure if it would help or not. I would also need somewhere to upload it to.

[Joulinar]

I don't thing it's needed to share the file themselves. More important what did you do to have it created 😉

[Doctorbeefy]

I'll mess around and see if I can recreate it. I am not sure if it happens when I add something to plex or if someone transcodes while watching it. I have quite a bit of friends and family using it.

[MichaIng]

Jep, from all I understood now, the new intro skip feature transcodes the media as well to scan for the intro, somehow logic 🤔. While the usual playback transcoding is done into a dedicated dir in /var/lib/.. and can be changed via settings, this intro detection transcoding is written to TMPDIR which is /tmp by default, together with other non-transcoding tmp data of PMS.

So I guess the 1.4 GiB file is a transcoded video for the purpose of intro scanning.

But maybe I got it wrong, maybe Chuck can clear things up.

[Doctorbeefy]

@MichaIng lol have to run another test looks like plex deleted it this time. Maybe they fixed it in the last update. It did add a rather large file though but it did not fill up my storage. I wonder if I add a bunch of stuff to the point where it gets full and it still trys to add stuff if that is causing it.

The image is what it does in plex when it adds the large file to tmp

EDIT: If I remember correctly the last two times it happened I was adding an entire anime series to plex. (Rather Large collections)

[Doctorbeefy]

root@DietPi:/tmp# ls -Al /tmp; du -ms /tmp/* total 108292 -rw-r--r-- 1 plex dietpi 110886990 May 27 16:49 d32e7a43-96f5-4480-85fc-b66912a085e5 drwxr-xr-x 2 root root 60 May 27 16:49 DietPi-Cloudshell drwxrwxrwt 2 root root 40 May 26 18:00 .font-unix drwxrwxrwt 2 root root 40 May 26 18:00 .ICE-unix drwxr-xr-x 3 plex dietpi 60 May 27 16:17 pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a drwxrwxrwt 2 root root 40 May 26 18:00 .Test-unix drwxrwxrwt 2 root root 40 May 26 18:00 .X11-unix drwxrwxrwt 2 root root 40 May 26 18:00 .XIM-unix 106 /tmp/d32e7a43-96f5-4480-85fc-b66912a085e5 1 /tmp/DietPi-Cloudshell 0 /tmp/pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a root@DietPi:/tmp# ls -Al /tmp; du -ms /tmp/* total 80900 -rw-r--r-- 1 plex dietpi 82837582 May 27 16:49 77869299-dec2-464f-bcb8-8bfbc6cea354 drwxr-xr-x 2 root root 60 May 27 16:49 DietPi-Cloudshell drwxrwxrwt 2 root root 40 May 26 18:00 .font-unix drwxrwxrwt 2 root root 40 May 26 18:00 .ICE-unix drwxr-xr-x 3 plex dietpi 60 May 27 16:17 pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a drwxrwxrwt 2 root root 40 May 26 18:00 .Test-unix drwxrwxrwt 2 root root 40 May 26 18:00 .X11-unix drwxrwxrwt 2 root root 40 May 26 18:00 .XIM-unix 80 /tmp/77869299-dec2-464f-bcb8-8bfbc6cea354 1 /tmp/DietPi-Cloudshell 0 /tmp/pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a root@DietPi:/tmp# ls -Al /tmp; du -ms /tmp/* total 118276 -rw-r--r-- 1 plex dietpi 121110606 May 27 16:49 77869299-dec2-464f-bcb8-8bfbc6cea354 drwxr-xr-x 2 root root 60 May 27 16:49 DietPi-Cloudshell drwxrwxrwt 2 root root 40 May 26 18:00 .font-unix drwxrwxrwt 2 root root 40 May 26 18:00 .ICE-unix drwxr-xr-x 3 plex dietpi 60 May 27 16:17 pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a drwxrwxrwt 2 root root 40 May 26 18:00 .Test-unix drwxrwxrwt 2 root root 40 May 26 18:00 .X11-unix drwxrwxrwt 2 root root 40 May 26 18:00 .XIM-unix 116 /tmp/77869299-dec2-464f-bcb8-8bfbc6cea354 1 /tmp/DietPi-Cloudshell 0 /tmp/pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a root@DietPi:/tmp# ls -Al /tmp; du -ms /tmp/* total 0 drwxr-xr-x 2 root root 60 May 27 16:49 DietPi-Cloudshell drwxrwxrwt 2 root root 40 May 26 18:00 .font-unix drwxrwxrwt 2 root root 40 May 26 18:00 .ICE-unix drwxr-xr-x 3 plex dietpi 60 May 27 16:17 pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a drwxrwxrwt 2 root root 40 May 26 18:00 .Test-unix drwxrwxrwt 2 root root 40 May 26 18:00 .X11-unix drwxrwxrwt 2 root root 40 May 26 18:00 .XIM-unix 1 /tmp/DietPi-Cloudshell 0 /tmp/pms-0122803a-67d6-4a46-b28e-f0bb5b0ecd4a root@DietPi:/tmp#

[Doctorbeefy]

That's only two episodes. I will test it a little more next time I add a crap ton of episodes. I am assuming that if temp hits 100% before it is done detecting intros that whatever handles the process in plex might crash causing the files to get left in tmp.

[MichaIng]

Great tests, isolating and documenting the issue perfectly! Good that in this case the file didn't get larger then something above 100 MiB, which is okay IMO. Also I now recognise that it is indeed a file and not a directory.
Remember here was a single file ~1 GiB (causing the crash).

The current intro detection included single series episodes, I guess over-length 4k movies are what could break things, if transcoding does not stop intelligently after a few minutes which are assumed to be enough to catch the intro 😉.

[MichaIng]

Other PMS users run into related issues and devs are already aware of it, hence there will likely be a solution soon 😃.

[MichaIng]

Issue has been fixed with recent release: https://forums.plex.tv/t/plex-media-server/30447/351