External ffmpeg process causing disk thrashing

[podonnell]

That server should be plenty fast in all regards.  If it were on Linux.

For a short period of time I was running Plex, and later Jellyfin, on Windows with a low power Intel J4205 as my CPU.  Whenever I played videos, even direct plays, Windows Defender hogged the CPU.  Like 60% just for Windows Defender scanning what Jellyfin was doing.  Because of this high CPU usage, and a slow-ish CPU, transcodes were out of the question.  Doing ANYTHING else on the server caused Jellyfin to buffer.

I'm wondering if what you're experiencing is the same thing.  Since watching via MPC-HC doesn't trigger the same Windows Defender behavior.

When you stream with Jellyfin, can you open Task Manager and monitor if the CPU usage spikes for Windows Defender?

Yep, watched the CPU and all other resources. Nothing goes above 10%. Oddly the transcoded videos that do make my CPU go up actually don't have the issue, but the direct plays that are only pulling direct from disk have the problem. 

This is definitely disk thrashing. The ffmpeg and jellyfin video stream are fighting over the read bandwidth of the hard drive.