Why does (did) formatting take so long?

I’m currently installing windows 2000 on a laptop for someone and it’s formatting the hard-drive ready for an install.

What does formatting actually do to the drive? And why does it take so long?

Isn’t it just a matter of writing a new file allocation table, which is a fraction of the disk’s size?

I can’t see any reason why it’d want to run over the drive and change each bit to zero. Would could it be doing?

It is (or at least it could be) also testing for and marking bad sectors. If you write blindly to these and then try to read back corrupted data, your system could crash.

A quick format plops down a blank FAT and calls it a day. A thorough format walks sector to sector and marks off any bad sectors it finds.

Obviously, this process can take a very long time on today’s huge drives. (As if it wasn’t tedious enough on a 200 meg drive!)

I remember it being tedious enough on a 360K floppy :frowning:

I belong to a financial services firm. At end of lease, or when reassigning computers, we gotta give them a DoD-standard wipe, 7 passes with random bytes. (It’s possible to recover data, with the right instruments, from a formatted disk)

Now, THAT takes awhile!

I work for one of those as well. We now require full-disk encryption on all desktop PCs and laptops. One side benefit is there’s no need to wipe drives.

Failing that, it’s often cheaper in terms of time to physically destroy disks and buy new ones if you need to be sure data is obliterated.