Dale Amon (amon@vnl.com) wrote :
[ snip ]
> It is a basic fact of life in a high performance
> file system that data is not written when you
> write to the file, it is written when something
> occurs to flush it to the media. I believe DOS
> wrote immediately and thus got around the problem.
> But floppies are slow, so you take a big performance
> hit for working directly with the media rather than
> a buffer.
Write-back with a short delay :
- no delays to the application
- ( almost ) immediate write to the physical media
> If you take an unsynced diskette out, it may not
> only have blocks not written, it may have the
> entire directory in a bad state.
OS never leaves the the medium unsynced :
- if there are dirty buffers , keep on flushing them.
This should not cause performance problems , because
it happens "in the background" , except if it is a hardware
problem , but IMO PC HW can have a floppy working with no
big impact on the rest of the system
[ 'NeXT sux' snipped ]
> I have a very low level of faith that systems like
> this can be made to work. Even if you have multiple
> disks and keep track of which is in, the disks will
> all be effectively corrupted unless loaded and synced
> before rebooting the computer or using the diskette
> elsewhere.
Solution : "uncorrupt" and sync the diskette before the LED goes
out.
-- David Balazic- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Wed Feb 23 2000 - 21:00:33 EST