Subject: Re: Work-in-progress "wedges" implementation
To: Daniel Carosone <dan@geek.com.au>
From: Jason Thorpe <thorpej@shagadelic.org>
List: tech-kern
Date: 09/30/2004 16:23:55
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On Sep 26, 2004, at 5:16 PM, Daniel Carosone wrote:

> Other random useful ideas, both of which probably belong in the
> userspace label-parsing-wedge-creating tools:

While I can understand how, at first, these might seem desirable, 
there's lots of reasons why you can't really do this.

Consider, for example, a partitioning scheme that stores multiple 
copies of its information for redundancy purposes.  GPT is one such 
format.

Also, for "unpartitioned space"... well, there could be multiple 
non-used extents of disk...  Really, a disk is partitioned or its not.  
And, even if you want to use "the whole disk" it is very desirable in 
this day-and-age to put some metadata on that disk anyway (see the 
hot-plug discussion).

>  - a implied wedge for "unpartitioned space", though perhaps it
>    shouldn't be usable as a filesystem.
>
>  - a very small wedge for the actual sector(s) occupied by the MBR or
>    other partition tables, to disabiguate update access to this data 
> and
>    avoid various special "skipping first block" schemes in filesystems
>    etc.
>
> --
> Dan.
         -- Jason R. Thorpe <thorpej@shagadelic.org>


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