Perhaps the most interesting application of this code is to put the journal on a solid state disk.
It is strongly recommended that either -m (mount-count dependent) or -c (time-dependent) checking be enabled to force periodic full fsck.reiserfs(8) checking of the filesystem. Failure to do so may lead to filesystem corruption (due to bad disks, cables, memory, or kernel bugs) going unnoticed, ultimately resulting in data loss or corruption.
Staggering the mount-counts at which filesystems are forcibly checked will avoid all filesystems being checked at one time when using journaled filesystems.
You should strongly consider the consequences of disabling mount-count-dependent checking entirely. Bad disk drives, cables, memory, and kernel bugs could all corrupt a filesystem without marking the filesystem dirty or in error. If you are using journaling on your filesystem, your filesystem will never be marked dirty, so it will not normally be checked. A filesys‐ tem error detected by the kernel will still force an fsck on the next reboot, but it may already be too late to prevent data loss at that point.
This option requires a kernel which supports incrementing the count on each mount. This feature has not been incorporated into kernel versions older than 2.6.25.
See also the -c option for time-dependent checking.