Re: Toronto Filsystem?
Werner Almesberger (almesber@lrc.di.epfl.ch)
Tue, 3 Mar 1998 16:54:57 +0100 (MET)
Trever Adams wrote:
>> From: "Benjamin C.R. LaHaise"
[...]
>> Actually, this is easier than it seems. A simple restriction that makes
>> everything work well is to require that all underlying layers be made
>> read-only, which avoids a mess of consistency problems. Then, use a top
>> layer that supports sparse files. Reading a file becomes: try layer one -
>> oh, not there; try layer 2... No, I don't have working code yet.
[...]
> Not cool at all. Once the original file owner updates the file (say the
> group agrees on a new standard, or root updates the file) any way but
> clean implimentation and write of the entire modified file becomes
> corrupted.
So you'd have to make "per-block COW" behaviour a mount option. With some
media (e.g. CD-ROM) you can be very sure that they won't change, so such
a shortcut is perfectly valid.
- Werner
--
_________________________________________________________________________
/ Werner Almesberger, DI-ICA,EPFL,CH werner.almesberger@lrc.di.epfl.ch /
/_IN_R_131__Tel_+41_21_693_6621__Fax_+41_21_693_6610_____________________/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu