Originally Posted by AcidWeb
There is a very high execution time difference between extracting M7 and KF8 part.
Creating MOBI7 from 373MB MOBI file (KindleGen output) take 2.34200000763 sec.
Creating MOBI8 from this same file take 103.877000093 sec.
How big is the output MOBI7 and how big is the output KF8?
If they are about the same size, it might be possible to do some optimisation.