Subject: Re: Embedded NetBSD Install
To: Luke Mewburn <lukem@NetBSD.org>
From: Vincent Jardin <vjardin@free.fr>
List: tech-embed
Date: 10/23/2004 10:58:39
In fact, using a Read-Only compressed GEOM architecture (see FreeBSD) or
a CRAMFS (see Linux), it could help to save lot of RAM memory instead of
uncompressing all the filesystem which is embedded into the Kernel :)

Regards,
  Vincent

Le sam 23/10/2004 à 04:32, Luke Mewburn a écrit :
> On Thu, Oct 21, 2004 at 11:49:42PM -0700, Loren M. Lang wrote:
>   | On Fri, Oct 22, 2004 at 10:30:08AM +1000, Luke Mewburn wrote:
>   | > For a functional NetBSD system you only need the `base' & `etc' sets.
>   | > It's possibly to cut down the install to just the shared libraries and
>   | > user programs you need, but that's an issue of "trial and error".
>   | > For example, I have a very functional embedded appliance that uses a
>   | > 10-20MB file system embedded in a kernel that ends up being 4-7MB in
>   | > size.
>   | 
>   | You mean something like a compressed ramdisk embedded in the netbsd
>   | kernel which expands to 10-20 megs in ram after it's booted?
> 
> Close; the in-kernel embedded ramdisk is not compressed per se --
> the overall kernel is.  When the system boots, the compressed kernel
> is loaded, uncompressed, and started, and once the autoconfiguration
> completes the root device becomes md0a (the embedded ramdisk).
> 
> NetBSD uses this technique for the NetBSD install media; see the
> framework in src/distrib.  Those generally use crunchgen instead
> of shared libraries, but otherwise the principle is the same.
> 
> 
>   | Also, how much does this system do?  The linux system uses the cf disk
>   | for it's fs, no ramdisk involved, and takes about 16 megs which includes
>   | apache and php.  Does netbsd do all that in around 16-20 megs?
> 
> I've made numerous configurations with more functionality in <= 20MB,
> including php + a web server (bozohttpd, which is much smaller than apache).