fsck and fstab

I remember either reading or finding some information a while back
regarding the mounging process at bootup. After a certain number of
system restarts fsck is forced. What file keeps track of this number? Is
it the same file that you can adjust the how often fsck is forced? I've
been trying to find it again and I guess my brain is toast. It must be
the end of the day or something.. :-)

Don