Database buildup very slow over 60,000 files (approx)

[guy]

Imatch 5;  I am buliding a new database that will contain around 106,000 pictures.
The scan time is very fast for the first 60,000 (approx.) files. Then, it turns very, very slow. 
  I can hear the hard disks starting to work very hard. I guess it will take over 12 - 15 hours to complete the job. The first 60,000 files have been scanned in about 1 hour.  The program has not been dismissed and I am not using any other program at the same time. 
The database is located on the disk C and the pictures are located on the second hard drive. My Dell computer is equipped with 32 Gb of RAM and a Intel i7 processor, Windows 8.1 
I've tried to build a second new database and the process is always the same; very slow after about 60,000 files.
Any tips ?

[Mario]

When importing this massive amount of data, you should run a Compact of your database to de-fragment it.
IMatch should show popups in the task bar, asking you to do this.
Just dismiss the loader overlay, run a Database > Tools > Compact and then IMatch continues automatically.