The e2fsck will regularly force a check of a filesystem even if the filesystem is marked clean. By default, this happens on every twenty mounts or 180 days, whichever comes first.
The ext3 filesystem does this as well, which can be annoying if you have a very large filesystem and a short downtime window. Therefore, it’s a good idea to disable this feature on large volumes. Keep in mind that you should still run fsck occasionally, by disabling the automatic checks, you get to Decide when, not the system.
Use the command:
tune2fs -i 0 /dev/hdxx
This disables periodic, automatic checking.