Differential Backup SLOW

I just got this program. I made an image of the main drive...it took 18 minutes.

Later that day I went to make a differential, and it indicates 35 minutes to complete.

Is this the worst coded backup program ever, in that it apparently reads each file one by one? Doesn't this program have an indexing/catalog system? Or does it need to recreate on the fly by reading both the backup and disk?

My other program completes a differential backup in 6 minutes max, or 1/3 the time of the original.

 

QuantumForce,

Please check Diff backup size. If it is much bigger than changed data amount, the most possible reason is that defragmentation was performed since full backup.

 

I have not had the patience to let the differential complete yet. There is no way that defrag happened...the drive in question is a SSD (Win 7 64 bit configured for solid state disks).