Hi jmhere,  On the Isilon cluster, each file has a logical size and a physical size.  The logical size is the size of the file prior to applying data protection.  The physical size of the file is the actual on-disk size of the file, with data protection applied.  For example, let's say you have a 6 KB file on a USB thumb drive.  When you ingest this file onto your Isilon cluster, OneFS would report its logical size to be 6 KB, and physical size would be bigger with data protection applied (mirrored for small files).  InsightIQ merely reports what OneFS reports.  Hope this helps.
InsightIQ - In the Capacity Reports, is Logical Size the logical size of the file or the capacity used on disk for first copy that includes the block overhead (8k for <8k files) but not the protection overhead?  I am trying to understand if a file of size 1k will show as 1k or 8k, a file of size 15k show as 15k or 128k? I cannot seem to find clear documentation on this.  OneFS version: 8.0.0.4 InsightIQ version: 4.1.1.3
InsightIQ - Is Logical Size the logical size of the file or the capacity used 
on disk for first copy?