Which distro and the differences between each of them

choosing a distribution is usually a matter of opinion. as far as which is easiest, that is also a matter of opinion. here's my opinion.

Debian uses up the least amount of disk space and is popular for servers. The Apache2 configuration is easiest to manage compared to many other distros. The Apache2 config is split up into different dirs and allows for modules or virtual sites to be enabled/disabled from the command line without modifying files by clever use of symbolic links. Debian 3.1 was released this year and addressed the problem with 3.0 being horribly outdated compared to most other distros. This is the distro I currently use.

CentOS is basically RedHat Enterprise Linux (RHEL) modified to remove trademarks. You'll find many books, documentation, etc. about this server-oriented distro compared to others. RHEL 3 wasn't exactly my favorite distro but RHEL 4 (CentOS 4) is pretty nice. IMHO, this distro is ideal for people using/learning Linux in order to find a Linux administration job or those interested in selinux. Linodes doesn't support selinux so I don't use this distro.

Gentoo is popular as a (primarily) source-based distro that allows for a high degree of customization and optimization–but it supports binary packages too. By comparison, distros like Debian don't exactly make it easy to optimize all the packages for i686 instead of using the default i386--Gentoo makes such optimizations (and more) painless compared to other distros.

Ubuntu is a Debian-based distro that is primarily popular as a desktop OS but they released Ubuntu for Servers 5.10 recently. They basically take a snapshot of Debian Unstable (latest packages) then test/stablize/release a version every 6 months while guaranteeing support for each release for a minimum of 18 months. Ubuntu came into being when Debian 3.0 was horribly outdated compared to almost every other active distro in the world. Think of Ubuntu as Debian + more up-to-date packages - proven trackrecord as a server distro. I don't think this will be popular on servers this year (2005) because Debian 3.1 was released--but I'm guessing it will gain momentum quickly in winter 2006 as Debian 3.1 ages.

Those are some great summaries.

It makes me wonder, has anyone around here actually tested the performance difference between a heavily 686+ optimized distro (ie Gentoo) vs a standard debian 386-optimized version (ie Debian), on UML/Linode?

My instincts tell me the CPU efficiency of the code is going to be virtually irrelevant, especially compared to memory efficiency, since more memory consumption implies more swap usage, which implies more IO usage. But I've never really checked. I don't know enough about the instruction set differences to know if there are some UML-friendly features that become available with the more modern processor optimizations.

I run Gentoo, but would suggest that a source-based distribution is not the best of ideas with a Linode.

For one thing, the updates requires compiles, which can be rather taxing on a Linode – memory (especially this!!) and CPU. Not much I/O hit. It's not much fun compiling large stuff like glibc on a "150 MHz" system. :-)

I would suggest a binary-based distribution with excellent package management systems and widespread support, such as Ubuntu or Debian. (Ubuntu is roughly described as Debian with newer packages, in essence.)

I've run RH, Slackware, and so forth for a long time but am less fond of them now. Ruined by Gentoo/Debian/Ubuntu, I'm afraid. :-)

Not as familiar with SuSE or Mandrake but have heard that Mandrake is great for the desktop, and SuSE being respectable.

With respect to Gentoo on a Linode, I don't believe you recoup your "time/resources investment" by compiling everything. You lose much more time spent building things than what little you gain from a slightly optimized binary running on a virtual machine.

The only real reason I run Gentoo is because I'm most familiar with this distribution at the moment. But if I could redo things, I'd personally probably go with Ubuntu on the Linode.