Hi: Porting Cramfs on FreeBSD

Eric Anderson anderson at centtech.com
Wed Sep 27 11:51:13 PDT 2006

On 09/27/06 12:44, Oliver Fromme wrote:
> Eric Anderson wrote:
>  > I'm currently working on a tarfs, that will do something similar to 
>  > this, except it allows you to use a regular tar file as the file system 
>  > image.
> That's cool.  I'm looking forward to it.
>  > I don't have compression working yet, but that is on the 
>  > roadmap. [...] large file system sizes (based on available
>  > memory)
> Hm.  Does that mean that the whole (uncompressed) FS image
> will have to fit into memory?  That would be a disadvantage
> compared to cramfs.  Cramfs doesn't compress the whole FS
> as one object (like .tar.gz), but it compresses it page-by-
> page, so every page can be uncompressed independently, and
> memory usage is very low, which is good for small embedded
> applications.

No, only inode+direntries need to fit into memory.  So an FS with 
1million inodes might take .5MB of memory (estimate).


Eric Anderson        Sr. Systems Administrator        Centaur Technology
Anything that works is better than anything that doesn't.

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