[olpc-software] Clarification please

[Dan Williams]

On Thu, 2006-06-01 at 09:19 +0100, Glen Gray wrote:
> Basically, I've been wondering why the OS seems to be based on a top 
> down approach (starting with Fedora Core 5 and stripping out a rough 
> guesstimate of whats not required) rather than a bottom up approach 
> (starting with nothing and using what parts of FC5 are required to 
> create a small, tailored OS).

It's not really top-down.  We start with a set of packages that we know
we are going to need (kernel, glibc, python, gtk, etc) and then use yum
to install those (and their dependencies) into a chroot.  Then, further
fine-grained stripping is done (glibc locale info, etc).  We know
[almost] exactly what the base set of packages is.  Plus, people keep
asking for more all the time.

You have to strike a balance between a completely forked OLPC distro,
and using an existing project's resources, like Fedora.  Seriously,
putting Fedora together is a full-time job for quite a few people, and
there's no reason to think that putting a forked OLPC distro together
wouldn't be a full time job for a few people too.

These machines aren't normal laptops, and they also aren't
PocketPC-class devices either.  They are somewhere in between.  You make
a tradeoff between the amount of effort you make in slimming down the
distro, and how much you benefit from upstream resources (ie Fedora).
If we fork it and go ground-up, we completely loose all the security,
development, and distro work that Fedora is doing.  If we go top-down,
we completely at efficiency.  You have to trade bits of one off against
bits of another.

You have to start somewhere.

> Using this approach would have allowed for a resulting system that had 
> rpm intact for use as the package manager and a more tightly tailored OS.

It's unclear whether there's a need for a package manager or not.
Updating will likely not be "rpm -Uhv xxx", but rsyncing files from
flash drives or the school server or whatever.  We all know the
downsides of dpkg/rpm/ipkg/yum/apt/etc, and I'm not sure anyone really
wants to inflict those shortcomings on children.  You have to ask, what
problems does having a package manager solve, and do children care about
those problems that _you_ think are problems?

The only real requirement here is to allow children to easily use
software they get from somewhere.  Note that I said "use", not
"install."  IMHO, you shouldn't have to think about "install", you just
get the software from a friend and use it.  And I also said "get from
somewhere," not "pull from a yum repo."  Because most kids aren't going
to be running synaptic, or pup, or whatever.  The software distribution
model here needs to be _vastly_ different than what we in the Linux
world are used to.

Dan