Subject: Re: DEV_B_SIZE
To: David Schultz <dschultz@uclink.berkeley.edu>
From: Julian Elischer <julian@elischer.org>
List: tech-kern
Date: 01/31/2003 16:13:13
On Fri, 31 Jan 2003, David Schultz wrote:

> Thus spake Julian Elischer <julian@elischer.org>:
> > > contents of the sector are there.  I think we would need to
> > > implement journalling to ensure integrity if hard drives were
> > > likely to corrupt sectors on power failure.  (How often do they do
> > > this right now, and how often would they with 4K sectors?)
> > 
> > 
> > in this case teh journel would have to not only include the block being
> > written, but data on each side of it that may be in teh same 4k.
> > that implies a read..
> 
> If you had to do that, then nearly every write would be a
> read-modify-write cycle.  It would be far less painful
> to use 4K blocks or larger and align filesystem blocks
> to disk sectors.

exactly..

But this is a case where "a filesystem using 512 byte blocks
would behave significanlty differently with one of these drives"

which is what he was asking.

>