Re: Idea: Use extended blocklist format to support installing to raid device.

[Robert Millan <rmh@aybabtu.com>]

On Tue, Aug 12, 2008 at 09:38:52AM +0800, Bean wrote:
> Hi,
> 
> Currently, the blocklist format can only support traditional disk. I'm
> thinking about a new format that can be used in raid as well.
> 
> The new format is like this:
> 
> checksum_0 blocklist_0 checksum_1 blocklist_1 ...
> 
> The checksum is the checksum of sectors in the blocklist that follows.
> For example:
> 
> c1 10+20,40+10 c2 10+50
> 
> This means 10-30,40-50 sectors from one disk, then 10-60 sectors from
> another disk. The checksum is used to find the correct disk.
> 
> For traditional disk, we can also use this format, for example:
> 
> c1 10+20,40+10
> 
> This can support install to different disk than the one core.img is
> in, as it will scan all disks for the correct checksum at runtime.

IMHO, I think we should try to get rid of blocklists, or avoid reliing on
them as much as possible.  Specially now that we have a good compression
ratio for msdos partmaps, and plenty of space on gpt ones.

-- 
Robert Millan

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