Directories at the center of the disk

From: Bill Pechter <pechter_at_monmouth.com>
Date: Tue Jan 12 20:09:24 1999

> It was thus said that the Great Fred Cisin once stated:
> >
> > Microsoft produced some "Stand-Alone BASIC" systems. They had file IO,
> > and used a a directory structure that was, in principle, similar to that
> > of MS-DOS, although they subscribed to the seek center fallacy of putting
> > the directory on a track approximately halfway towards the center.
>
> What's the fallacy in putting the directory in the center of a disk?
> Seems to me it would cut down on average the seek time.
>
> -spc (The elevator algorithm favors the center of the disk in fact)

We used to put the OS/32 directory in the center for optimization.
Early Unix admins put /usr in the center of the disk (or /swap)
to minimize seeks.

DEC did the same, I think on some OS's.

Also, I always felt putting the directory at the beginning or the
end of the disk increased the possibility of data loss through head crash
since the beginning of the disk was a common crash point at load time
with dirty packs and the end of the pack was where the bad sector
data was and was an area where I didn't want a lot of action.

Bill
---
  Bill Gates is a Persian cat and a monocle away from being a villain
  in a James Bond movie                              -- Dennis Miller 
  bpechter_at_shell.monmouth.com | pechter_at_pechter.ddns.org
Received on Tue Jan 12 1999 - 20:09:24 GMT

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