Oh right! In admin console under server>general at the bottom there is a section called “performance”. Under this the first entry is “parallel library scan tasks limit”. Increasing this can significantly improve performance here. If it’s empty it is auto selecting. To that point if you’re running jellyfin in a docker and only allow it access to one core that would seriously limit performance here. Screenshot below, I currently have it set to 2 because I’ve done the “big” scan and I don’t need my cpu hammered when jellyfin does library scans

Additionally an issue I ran into later: under playback>transcoding enable hardware transcoding must be checked. Trickplay task was taking literal months because even though I had configured igpu transcoding correctly this has to be enabled separately. UX stuff like this is where jellyfin needs more polish; I’m sure there’s debate about this but why would this not default to on once transcoding is enabled? Who knows. Maybe just oversight.

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