Which rule runs CollectLogicalDiskStatistics.vbs?

Running SCOM 2007 R2.

We have issues with CPU spikes every 2 hours and I have tracked it down to the “Disk Defragmenter” service and is pretty sure the culprit responsible for starting it is CollectLogicalDiskStatistics.vbs and the line:

intRC = objVol.DefragAnalysis(boolDefrag, objRpt)

The trouble is, that I cannot find the rule kicking off the script – the Collect and Collection rules for Logical Disk I found all use the “Statistics DS” datasource and don’t seem to reference the script… But what starts it then?

Anyone?

Thanks!
Nicolaj