Haha. Might have slightly exaggerated. But only slightly.
The Proxmox host in question has a 1Gbit connection to the NAS. (Unfortunately. The other hosts don’t have a GPU, but SPF+… Oh well, can’t have everything.)
At some point in the last couple of months, it must have been damaged, and negotiated down to only 100Mbit. This must roughly have coincided with the Jellyfin 10.11 update, since I remember thinking that it must be the cause, due to close proximity of update and first issues.
Anyways. For basically everything in my library, 100Mbit is fine. Streaming an episode NAS->Jellyfin and Jellyfin->TV at the same time basically never saturates the link.
BUT, from what I’ve gathered by digging through Jellyfin issues and PRs, there’s a separate issue where Jellyfin will pull the episode, and if you need subtitles extracted from the episode file server-side (to transcode them in, if the clients can’t play them), it will at the same time pull the episode AGAIN, and together with the Jellyfin->TV direction, that’s frequently enough that it saturates the link.
Symptoms is (was) either a 20-30s wait before the episode would start playing, or complete freeze.
However, I believe this particular issues has been solved for a while. I’m not sure, because I instead opted for the Subtitles Extractor Plugin, which runs nightly and pre-fetches all the subtitles and stores them on the Jellyfin VM itself.
Where it was still noticeable though was if one of [Library Scan/Trick-play Extraction/Subtitle Extraction/Media Segment Scan] ran while playing an episode, the server would completely lock up.
Long story short: cable swapped, 1Gbit, all issues gone.









Does it actually? My VM has a lot of RAM, and Proxmox reports usage always around 90%, but that’s no matter how much RAM it ACTUALLY has, because almost all of that is cache and not strictly necessary.
free -mshows Jellyfin using maybe 2 Gigs.