About file systems and formats

[Andrew Falanga]

On 3/29/07, Ivan Voras <ivoras at fer.hr> wrote:
>
> Andrew Falanga wrote:
> > Yesterday while working on a problem at work, a colleague and I were
> > talking
> > about the various file systems and something that I have always wondered
> on
> > is what are the various file systems doing when a format is being done.
> > For
> > example, at home, my PC has 2 80gb drives.  One for Windows and the
> other
> > for FreeBSD.  It took Windows nearly an hour (give or take) to format
> the
> > 80gb drive.  On the other hand, it took FreeBSD little more than 3 - 5
> > minutes to format its 80gb drive.
>
> This is too slow for the FreeBSD case. By default, Windows will do a
> full format - in effect, will write zeroes all over the drive, with the
> intent of checking if the drive is capable of it. Unix format (newfs)
> will only initialize file system structures - in effect, will write out
> (initially empty) file tables to the drive. This takes about 5-10
> seconds on 250 GB drives, so 3-5 minutes you got is way too much.
> There's no way of making newfs to the "checking" phase; there are
> separate utilities for that.


Wow, I guess so!  I did this some time ago and was trying to be conservative
in my time table as I actually couldn't remember the exact time.


> my colleague and I because there such a speed difference in formatting
> > things (once windows is installed) when choosing between a "Quick
> > Format" or
> > a "Full Format".
>
> Yes, Quick format will just write the file tables (this is simplified,
> but you'll get the picture) on Windows, too.
>
>
>
Sounds like we were on track.  The system just creates the appropriate data
structures using newfs and one can use the smartmon Chuck mentioned to keep
track of the surface, i.e. looking for disk defects.

Thanks for the links to the source (Chuck).

Andy