alexchamberlain
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First MB

Tue Jul 10, 2012 12:34 pm

On the Arch image, the first MB is unused. What is the reason for this?

It is the same with the Debian image.
Developer of piimg, a utility for working with RPi images.

asb
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Re: First MB

Tue Jul 10, 2012 12:35 pm

You want to align your partitions to the SD card erase blocks (which are typically 1, 2, 4 megabytes). The wheezy images align partitions to 4MiB.

alexchamberlain
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Joined: Thu Jun 14, 2012 11:20 am
Location: Leamington Spa, UK
Contact: Website

Re: First MB

Tue Jul 10, 2012 12:37 pm

asb wrote:You want to align your partitions to the SD card erase blocks (which are typically 1, 2, 4 megabytes). The wheezy images align partitions to 4MiB.
I see, and you can't use the first MiB because of this? (0 is a multiple of 1, 2 and 4, right?)

What are erase blocks?
Developer of piimg, a utility for working with RPi images.

asb
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Re: First MB

Tue Jul 10, 2012 12:41 pm

Take a read of: http://lwn.net/Articles/428584/

You can't stick the first partition starting at 0 bytes because you need the partition table.

alexchamberlain
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Joined: Thu Jun 14, 2012 11:20 am
Location: Leamington Spa, UK
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Re: First MB

Tue Jul 10, 2012 12:49 pm

asb wrote:Take a read of: http://lwn.net/Articles/428584/

You can't stick the first partition starting at 0 bytes because you need the partition table.
I'd completely forgotten about the partition table! Thanks!
Developer of piimg, a utility for working with RPi images.

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