DS216j very high CPU usage - normal?

server-synology

#1

I've been running my server on a Win 10 media PC, storing the files on my DS216j. For a number of reasons, I've moved the server onto the NAS and I've seen CPU usage constantly between 85-100% ever since the new PMS went live. Is this to be expected?

I'm aware that the NAS is severely underpowered for PMS, but I'd have assumed that it'd be idle much of the time. I wasn't able to transfer the old server's data (thumbnails, viewing history, preferences) to the new machine, so I assume it's spending a lot of time rebuilding all that metadata. Should I expect to see the CPU usage drop once it's finished? For reference, I've got about 200 movies, 1600 TV episodes, 4000 audio tracks and an HDHomerun Connect with about 110 channels' worth of program guide to maintain.

Thanks in advance.


#2

Yes, cpu & ram usage will drop after finishing with the library operations.


#3

I hope so. I’ve finished moving stuff around now and Plex isn’t showing any scans or EPG updates in progress (though it is recording one program) and the CPU is still pegged at 99%.

Currently, PMS’s Status view is showing the last alert as “finished processing x” with a timestamp 30 minutes ago, but the resource monitor in DSM is still showing two Plex Media Scanner threads, each running at 35-50% CPU (with occasional dips into the 20s). I’m curious as to why they’re not showing up in Plex.

I guess I’ll give it a day or so and check again - surely that’s enough time for it to have finished doing whatever it feels it needs to do with the media - and see where the CPU usage goes after that. I’ve already disable partial scans when changes are detected, limited periodic library updates to daily, thumbnails to scheduled tasks, disabled the update of all libraries during maintenance: I’m assuming that will reduce the amount of work it has to do, though it hasn’t seemed to make any difference yet.


#4

What I have seen is that regardless what you have chosen at scheduled tasks for thumbnails, the first scan to a new library has to make thumbnails for every video. This will take more than 2 days with your library on DS216j. I would say give it a week to see how DS216j is behaving then. And in the meantime, try to not make any major changes to pms settings or restart/shutdown DS216j.


#5

You can turn off, as well as delete, those thumbnails in ‘Advanced’ under Library - Edit - Advanced. You prevent them in that same popup prior to building the library.


#6

@gdion said:
… This will take more than 2 days with your library on DS216j. I would say give it a week to see how DS216j is behaving then. And in the meantime, try to not make any major changes to pms settings or restart/shutdown DS216j.
This seems about right: it’s been a little over two days since I made the transfer and CPU use is much lower. I’m still seeing spikes up to about 50% (one core’s worth, I guess) when PMS is busy, but I’m also seeing idle periods as well. I have had to restart PMS once in that time, though, because it wouldn’t finish a recording.

@ChuckPA said:
You can turn off, as well as delete, those thumbnails in ‘Advanced’ under Library - Edit - Advanced.
Yeah, but I like having them, when they actually appear (I’m not seeing them in the Xbox One app right now, though I’m sure I have in the past).


#7

If you’re not seeing them on the Xbox then, unfortunately, I can’t help you here in the server-side of the forum. I can only suggest you go to the Xbox forum and look/ask there.


#8

Will do, if I can determine if it’s some or all videos.