Originally Posted by Vortex
I have an i3 3.3Ghz, 8Gbs ram, 7Tb's of HDD. I tried adding 155,000 files into Calibre, it was managing about 1% an hour.
It is nuts to try and do these in a giant batch. Try lots of 1000, 2000 or 5000 instead. You may find a magic level that maximizes the speed at which books will be added.
Personally I would recommend a 1000 at a time, followed by fixing the metadata for that batch before moving on to the next batch. Fixing the metadata is far from automatic, it requires eyes on the data and books. Once the batch is complete move onto the next.