I usually leave a gap of several days. Simply to digest what I've read. If a book doesn't require a rest period, it's probably one in a series, you skimmed it in order to tell friends you've finished it or it was complete bobbins
This is a response to Wonders Disciple. I brought Birdsong on recommendation but never made it past the affair (3rd chapter?). The story seemed a little hurried and Faulk's style doesn't endear itself to the literary canon it occupies.