replied on October 17, 2014
Each and every OCR Process will consume all the CPU cycles it can on *one* processor.
Most of the time with QF Agent I recommend at least 3 cores, since up to two OCR processes can be run at once. Quick Fields can execute more than 2 QF sessions at a time but if there are OCR or Zone OCR in the QF sessions those threads can only run up to 2 times simultaneously on a particular machine (this is a license restriction between Laserfiche and the makers of Omnipro). I've run into issues with this where sessions time out mid stream if I have lots of OCR and try to bump it over 2 so most of the time I limit my customers to 2 QF agent sessions at a time.
So if you follow that logic, 3 cores is usually sufficient because the 3rd core is your OS and other overhead. Since your screenshot shows 2 cores that's probably what's happening. Outside of the OCR process QF doesn't tax the processor too much as long as you have it installed on a local hard drive (not on a network hd, it can thrash a network connection with all of the file writes it does temporarily).
Incidentally the 2 OCR sessions at once apply for ANY LF product. So if Import Agent is running on that same machine that can steal slots of OCR from Quick Fields since all of them use Omnipro. But that's what multiple VM's are for, right?