Does this show the cause of the OP's issue : 'During system boot, the file /etc/modprobe.d/zfs.conf is auto-generated to limit the ZFS ARC to 1/8 of installed memory. This can be overridden if necessary by creating a custom 'config/modprobe.d/zfs.conf' file. Future update will include ability to configure the ARC via webGUI, including auto-adjust according to memory pressure, e.g., VM start/stop.' About | Unraid DocsAbout | Unraid DocsPlease add additional guides on how to use and configure ZFS in this subfolder