Plex lags when playing movies with changed artwork

[Lock_Robster]

Server Version#: 1.23.5.4801
Player Version#: All Plex clients

I have discovered an issue with Plex running very slow and lagging when playing a movie that has had it’s artwork changed.

When movies are added to a library, they all automatically fetch artwork. If I play those movies, they show up in Plex Dashboard under “Now Playing” instantly (less than 1 second). If I stop those movies, they instantly disappear from the Dashboard and “Now Playing”.

Selecting one of those movies that would work “instantly” and changing the poster to anything (doesn’t have to be a custom downloaded image/url, doesn’t make a difference), then I play that movie again. The movie doesn’t show up in Dashboard for anywhere between 20 seconds and 2m30s (maybe longer, I didn’t test every movie).

If I stop the movie, it doesn’t disappear from the Dashboard/Now Playing for roughly the same time it took to show up in the Dashboard when playing the movie.

During this “lagging” period, Plex players become unresponsive when trying to play a video. It either buffers during that whole time, or it shows an error. Once the movie finally shows in Dashboard, then other Plex players can play other content as fast as it is normally.

I discovered this issue after setting up Webhooks. I configured my lights to turn off when playing video on Plex. I was watching TV Shows/Movies and everything worked instantly. I then came across a movie that didn’t turn my lights off after playing it. Then after about 2 minutes the lights finally turned off.

This is when I got into testing and found it had to do with movies that I had changed the artwork for. Webhooks on/off doesn’t make a difference.

If I “Refresh Metadata” on one of the “slow” movies that I changed artwork for, then they go back to working instantly again. Even though the refresh keeps my custom poster. So the only temporary solution is to ‘Refresh Metadata’ on every movie that I change artwork for. Otherwise it will lag out Plex.

Quick recap:

Default Artwork: Updates Dashboard/Webhooks in ~1 second
↓
Changed Artwork: Updates Dashboard/Webhooks in 20-270 seconds
↓
Refresh Metadata: Updates Dashboard/Webhooks in ~1 second

[Lock_Robster]

I just some more testing.

Looks like the movies don’t have to change artwork for this issue to occur.
I believe this issue is with the cache of all ‘selectable’ artwork for a movie.

Editing a movie and selecting ‘Poster’ will bring up a page that auto fetches a bunch of posters from the selected agents. You can see them all download in a few seconds.

Without changing artwork, you can close the edit dialog and play the movie, right away there are lag issues and the movie takes a while to show in Dashboard.

I believe this is why some movies took way longer (2m30s) than other movies, because those movies had more available posters listed. Opening up the ‘Background’ dialog in the ‘Edit’ window, also downloads the list of available backgrounds. This also stacks time onto the ‘lag’ time of playing/stopping the movie.

After loading all the available artwork in the ‘Edit’ window, every time you open that window, those posters/backgrounds no longer have to download, they are already loaded (cached). ‘Refresh Metadata’ will clear that cache, going back into ‘Edit’ will show the posters downloading again.

Server Settings → Manage → Troubleshooting
‘Optimise Database’ - Doesn’t improve speed
‘Clean Bundles’ - Doesn’t improve speed

[Volts]

That’s completely insane.

I can’t duplicate it on FreeBSD/TrueNAS.
[Edit: I can, barely.]

/subscribing

Is there any possibility that antivirus software is going nuts when Plex interacts with those files? Temporarily disable it, or whitelist/exclude the Plex dir?

Edit2: OK, maybe I can partially duplicate this. Even on movies with a LOT of posters and backgrounds, it’s only a second or three.

It’s just an extra couple seconds. But it’s not instant, like it is after a Refresh Metadata.

That’s completely bizarre. I didn’t want to believe it.

[Lock_Robster]

I’m not using any anti-virus on my pc.

In case it’s relevant, the server is running on Windows 10 on a 2TB SSD. All media is stored on a Synology NAS. Everything is connected via Gigabit Ethernet.