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Date: Sun, 19 Oct 2003 01:35:51 -0700
From: William Lee Irwin III <wli@holomorphy.com>
To: Hans Reiser <reiser@namesys.com>
Cc: Larry McVoy <lm@bitmover.com>, Norman Diamond <ndiamond@wta.att.ne.jp>,
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Subject: Re: Blockbusting news, results are in
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Larry McVoy wrote:
>> I've told you guys over and over that you need to CRC the data in user
>> space, we do that in our backup scripts and it tells us when the drives
>> are going bad.  S

On Sun, Oct 19, 2003 at 12:08:00PM +0400, Hans Reiser wrote:
> Why do the CRC in user space, that requires modifying every one of 7000+ 
> applications (if I understand you correctly, which is far from a sure 
> thing;-) )?
> Write a reiser4 CRC file plugin.  It would take a weekend, and most of the 
> work would be cut and pasting from the default file plugin..  
> I understand why you do it in BK, but for user space as a whole user space 
> is the wrong place.

I think the fs driver layer might be the wrong thing too; maybe it'd be
best to do the CRC and/or checksumming at the block layer?

At the very least, I see a lack of genericity with respect to making it a
plugin to a specific fs. I'm going to try not to delve too far into
specifics, as my knowledge in these areas is limited, but I'd welcome any
corrections of misunderstandings I might have about feasibility, value,
or importance of these things, and even techhical misconceptions.

Jens, I apologize if advance if this is just another lame flamewar best
bitbucketed as opposed to answered.

Thanks.


-- wli