TL;DR: After upgrading to Unraid 7.2.0, a single MakeMKV export on a 2× Crucial P310 ZFS mirror stalls every 5–10s (%util=99%, w_await=25ms). All other Dockers off. Downgrading to 7.1.x restored 500+ MB/s with zero throttling. ARC was auto changed to 2GB after upgrade: ARC size: 2.0 GB (capped despite 32 GB RAM) ARC miss %: 27.9% Test Result All other Dockers stopped No change zfs set sync=disabled No improvement recordsize=1M, atime=off Minor help, not fix G6 camera in HA paused No impact