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High CPU & Disk Writes - Printable Version

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High CPU & Disk Writes - lovestha - 2023-11-15

My Jellyfin instance is frequently very sluggish (home page takes a minute to fully load) and CPU usage is high (50% of one core) and many writes are being done (50Mbps)

I thought it was library scan related, but I've started noticing it when it isn't scanning.

Running 10.8.12 using docker on OpenSUSE Tumbleweed.


RE: High CPU & Disk Writes - tmsrxzar - 2023-11-15

"openSUSE can run on any desktop or laptop PC, even those 20 years old devices!" https://en.opensuse.org/openSUSE:Hardware_FAQ

that doesn't narrow it down, maybe it's normal for a 2003 Pentium 4; not normal for a 2023 Intel Core i9-14900K

best not to assume everyone knows what hardware you have


RE: High CPU & Disk Writes - TheDreadPirate - 2023-11-15

Hardware specs and logs, please.


RE: High CPU & Disk Writes - lovestha - 2023-11-15

CPU: i3-8100
RAM: 32G
OS & database: Crucial P2 500G (the high disk writes are this drive, nearly no activity on others)
Libraries: Local BTRFS on HDDs: 2x(meta RAID1-C3 & data RAID1 on three drives)

Will posts logs in a couple of hours.

History: I've been running jellyfin on these libraries for years, but since I consolidated down to a single server (the jellyfin instance used to mount the libraries over NFS) I've been seeing this behaviour. The only change to the system is that I've added more services (that are idle when this is occurring) and a lot more RAM.


RE: High CPU & Disk Writes - lovestha - 2023-11-15

Glancing towards logs has me suspicious: why are so many transcodes occurring.....


RE: High CPU & Disk Writes - lovestha - 2023-11-23

Okay, transcoding is not all the issue, no transcoding occurring right now, and 44% CPU 30~80Mbps writing to database (or transcode output dir, but I'm certain no transcoding is occurring, last transcode log was 5 hours ago)

It is doing a scan of the TV library, but shouldn't have much to write to the database, there shouldn't be more than 10 new episodes.

(I did do a complete rescan and replace of the YouTube database earlier in the day, but that completed many hours ago)

Log: https://files.cerberos.id.au/s/Pp5sHjXydbRAxSq


RE: High CPU & Disk Writes - TheDreadPirate - 2023-11-23

There's a lot going on in the log. Lots of failures regarding some json files it can't find anymore. I'd imagine that is contributing to the higher CPU and disk usage.


RE: High CPU & Disk Writes - lovestha - 2023-11-23

The missing .temp.json files are all in the YouTube library refresh that completed successfully. And another refresh of it doesn't have any log outputs.

I just don't get what a scan for new and updated files needs to write that much for.


RE: High CPU & Disk Writes - Kubwa - 2023-11-30

Can you check if the writes are going to the library.db file of jellyfin? I had that problem. It is caused by the journaling mode chosen by jellyfin. it was so painfull in my installation, i had to fork jellyfin and change the journaling mode myself to wal.