The time he gets out depends on the way their parole system is set up.
It would be one of the three ways:
* 1/3 jail time; 1/3 remission; 1/3 parole, so a person would be out after a third of the sentence.
* Depends on the jurisdiction, the above could apply only to sentences of 6 years in total or less. For sentences above 6 years, there's no remission, so the person has to spend 2/3 of the sentence in jail.
* 1/2 jail time and 1/2 parole
* he'll most likely qualify for 6 months of work release too at the end of the jail time
Regardless, unfortunately, prisoners with such long sentences don't qualify for minimum security, regardless of the crime. He will be assesed every 6 months, probably will go to medium, and in a few years to minimum.
Unless he has connections at assesments, which hopefully he does
No matter what, he will be doing it hard now. Good luck to him.