In bulid-in cappacity reports I noticed that volume utilization value is different from the total qtrees utilizations for this volume. In other words: I have utilization report for vol001 and I have utilization value. And when I take report for qtree utilization for vol001 and sums up values I receive different utilization value.
1. Volume always consider Storage Efficiency (Dedupe + Compression) while reporting used capacity, so the reported used capacity is always less than or equal to the actual data written on the volume.
2. Qtree Used capacity is always the actual data written on the qtree. Hence when the Storage Efficiency is 'Enabled' on the volume the numbers added for all the qtrees will not match with the number shown for the volume. The qtree numbers will look bigger than that of the volume.
3. The numbers will closely match when Storage Efficiency is 'Disabled' on the volume, but still will not be the same, as Volume also consider - metadata, snapshots, and some other savings.