Hi,
I’ve noticed that every day at scheduled task time Plex maybe deep analysis JUST SPECIFIC 2 files. I’ve noticed that for a few days. But I’ve disabled all kinds of analysis except intro detection on Plex. Then why it’s doing this? It’s causing high CPU & ram usages that time. How to fix this problem?
Note: I’ve manually analyzed those 2 files through Plex web just for checking & it was completed successfully too.
I’ve collected the below processes through my monitor script.
You can’t disable the deep analysis PMS does, this is required for PMS to operate properly. The “analyze” function in Web is a quick analysis, not the same thing. Part of the deep analysis is to check the bitrate of the streams to look for spikes that may cause issues. If this is getting stuck on these 2 specific files, it is likely that there is an issue with the files that this analysis is failing on.
We would need to see the file to check why it’s failing. My guess is that since these are multiple episodes combined into 1, there is an issue on how these parts were joined so the analysis is failing at that point.
I never could find any detailed information on “Plex Media Fingerprinter” so I’ve just been disabling it with chmod -x after every update. Plex is still working perfectly fine. I don’t use intro detection or thumbnails. I don’t know when that fingerprinter got added but it takes up a bunch of CPU doing it’s thing and I got tired of that spike during maintenance time every night. There is not much information available as to what it’s actually doing or why it’s needed.
It generates a digital fingerprint of the audio. It looks for that same fingerprint in subsequent episodes. When a match is found, that’s considered the intro. That does take cpu power to perform this.
Edit - Have you heard about the sonic analysis PMS can do for your music. This is similar but in a much simpler way.
In my attempt to keep space usage reasonable for plex I turned off intro detection, chapter thumbnails, and anything related to media analysis. I disabled the media fingerprinter executable because I didn’t see any benefits from it & I definitely noticed the increased CPU usage during maintenance times. Space usage for plex config volume on docker been stable at 24GB. Much better than my previous install that had crept up to almost 500GB. It sucks losing access to nice features but that was just way too much SSD space being wasted.
I have no plans to add my music collection into plex anytime soon. It’s full of stuff ripped over the years that is not properly tagged. Fixing it all is so very boring so it could be years until I finish with that, lol.
Intro detection should not take up that much space. There was an old bug where the temporary files Intro Detection would create were not getting removed after it was done. This should be fixed now.
Chapter thumbnails are small. If you have 10 chapters, that’s 10 small images that maybe is a few MG total. Unless you have like 20,000 episodes and movies, this would not account for 100’s of GBs.
Media analysis only results in saving a small amount of text into your database. This also should not be significant in space.
When I switched to docker I started with chapter thumbnails, intro detection, and lots of other scheduled items disabled to keep my install small but still kept seeing space usage increasing slowly every night & the only process I could see using up tons of CPU during the scheduled task time window was plex media fingerprinter. I chmod -x’d it and my CPU & space usage has been stable since. I also have no clue why it kept running even though I already had intro detection & extensive media analysis disabled everywhere.
My old plex had been migrated from CentOS 6 up to 8 but I deleted it months ago so no clue where all that space was being wasted. I used to just move the vmdk containing /var/lib/plex between VMs when upgrading due to the size & number of files.
I think the fingerprinter still runs to generate the needed info, it just isn’t live until you enable the intro detection. The space used should be minimal, unless like I said and you had the old buggy version that wasn’t cleaning up after itself. That space issue should be gone now, but the process does still run.
