Messages like this:
Dec 11 08:51:04 Raptor emhttpd: read SMART /dev/sdj
mean that we have detected I/O on a device that has been previously spun-down. We issue a 'smartctl -A' command to the device (which is now spun-up) to read its temperature. Probably this would be better wording:
"I/O detected on device /dev/sdj, reading SMART"
Probably a plugin is responsible for this.