There is one question which is bothering me alot: It is said that data can only be held on magnetic disks for about 5 years. After that, it could get lost because the magnetic force on the disk gets "weak" (I do not really know how to describe it better ;))
Do disks counteract against this? For example: Do they rewrite all their bits from time to time when they are idling?
Regards Christian
Writing to a disk takes time and a disk will wear from excessive writing. Although with an SSD this is much more troublesome than with a harddisk, it still happens.
So to answer your question, no a harddisk does not rewrites itself to maintain coherence.
No, being in computer science for more than 20 years I never heard about such a mechanism.
However it is uncommon that a hard disk driver is used this long.
(also Disk de-fragmentation process rewrite (move) part of the data but not all)
