Re: Zero-clearing all zero-clearable bytes.

[Phillip Lougher]

Tetsuo Handa wrote:
> Hello.
>
> I often create a Live CD.
> When creating a Live CD, loopback mounted ext3 image files are used.
> These image files are then compressed so that the ISO image will fit within
> a CD-R's capacity (i.e. 700MB).

You don't mention what you're using to compress the ext3 image file.  If 
you're using Squashfs then it's much better to zero-fill the blocks 
rather than use 255, because Squashfs detects zero-filled blocks and 
stores them sparsely.  This not only gets slightly better compression 
(than a compressed zero-filled block), but reading is also slightly faster.

Phillip


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