Sabayon Linux is an interesting distro. It is based on Gentoo, which is a favourite of many but seeks to eliminate some of the compilation hassle of Gentoo by providing a live CD and an installer that installs precompiled packages.

A desktop Gentoo install would be up and running in a day or so, whereas you can get Sabayon installed and running as quickly as any other distro – the install time is a function of the number of packages you install.

So how does it work in real life? Well, installation is indeed a breeze – using the mini-CD option you are up and running in no time.

The mini-CD has a subset of the full Sabayon install DVD, which comes in at 3.3 gigs. The Sabayon team say that they have eliminated all the “useless” things to make the mini version. These useless things are presumably included on the DVD.

So once you have installed, you will want to add a few of your own packages. And this is where things get interesting. Firstly Sabayon has a release schedule, and an existing Sabayon installation can be upgraded to the new release, though only those packages that are part of the distro. I would imagine this would often cause non-Sabayon packages to break.

However, if you are happy to manage this, then install some extras. But this is where things get tangled. For example, it is recommended that an

emerge –sync
layman -S
emerge –newuse –update –deep world

is performed to get everything up to date. This is pretty important as anything you want to install over and above standard Sabayon, is likely to have library version dependencies that are not met by the install disk libraries.

So what happens here in effect is that everything in standard install is almost immediately replaced by updated and recompiled versions. And something is bound to want to look at the kernel in /usr/src/linux, so you had better put one there. And build it. And then install it (thankfully Sabayon does provide the .config file for the default kernel in /proc/config.gz). But the whole point of Sabayon is to not have to do this… I had around 6 gigs of downloads once I had updated everything.

But then there is something else Sabayonic that comes into play. Sabayon states that it is cutting edge – and it is – it comes with late release Nvidia and ATI drivers, and aiglx, xgl and beryl are there out of the box. But in order to be cutting edge, masked packages need to be accepted.

Masked packages are flagged with ~amd64 or ~x86 depending on your architecture. These are packages that have not been fully tested and so it is up to you if you want to risk installing them.

A sabayon default installation has “ACCEPT_KEYWORDS=~amd64” in make.conf, which means that it will emerge anything in testing. This is how it achieves cutting edge-ness. But obviously, not everything in testing will work – that’s the whole point of testing it. So the emerge will fail on various packages, which will cause you to try and find a path through the dependencies that will allow everything to work – by managing what goes into /etc/portage/package.mask. This is pretty difficult.

And it seems to me that it is impossible to go back to not bring in untested packages. Well, not impossible, but hard. The keyword can be switched off, but then everything needs recompilation. But some of the libraries cannot be downgraded – you are warned that downgrading will break the system – like Glibc.

So anything that relies on a library that is currently in testing cannot be downgraded must by definition be an “in-testing” package. So trying to unravel the dependency web is intractable.

Having Gentoo on the desktop is pretty cool, and Sabayon does a good job of getting you there – but the nature of Gentoo is that you are compiled to your architecture, so having precompiled binaries doesn’t give you any of the benefits that Gentoo is about – except emerge’s excellent dependency management. But that demands that you recompile everything, which then makes Sabayon redundant.

Perhaps the better approach would be to install vanilla Gentoo, then use layman to bring in the sabayon overlay, and use the Sabayon part of the portage tree to bring beryl and all the extra goodies that make Sabayon worthwhile.

Thursday, June 14, 2007

« Back