I suppose one argument might be that it's hard to define a universally accepted list of packages that a VM-only install needs. But that's perfectly OK because it's usually easier to craft a list of required packages that need to be installed after the base than it is to prevent the default installation of a ton of packages you don't need. After a reboot, it's a one-liner to install whatever tools you need on top of a minimal base layer.
It's also much more daunting to start cutting an already-installed system. You tend to err on the side of caution (who knows -- that DNS server might need CUPS at some point, right?), and even those who are somewhat vigilant about trimming their installs will stop short of custom kernels because it's too much hassle. However, if there were a kernel-virt RPM that handled that automatically, it would be a different story. Further, odd default decisions are made in many distros -- such as Ubuntu Server 12.04 deciding that if you want to install GNOME, you probably want the Transmission BitTorrent client too, or RHEL installing the xsane scanner front end.
Lastly, there's the "who cares?" concept. Most admins won't bother to hoe out a default installation and remove the unnecessary stuff. Yes, we have tons of storage, but slimming down a VM install from 2.5GB to 500MB without losing any functionality becomes a very big deal at scale, especially when backups are factored into the equation. Further, it greatly reduces the time required to move these VMs around between storage arrays.
Perhaps I'm being overly critical and this is a picayune matter for many people. Still, I can't help but shake my head when I look upon a sea of Linux VMs that are all well equipped to handle ARCNET and Token Ring network adapters right alongside PCMCIA SCSI adapters that haven't been manufactured in years. But hey, at least that DNS server VM is running smartd "just in case" and can access an ancient parallel-port scanner. Heck, it probably has a full assortment of games installed too.
This story, "Linux fatware? These distros need to slim down," was originally published at InfoWorld.com. Read more of Paul Venezia's The Deep End blog at InfoWorld.com. For the latest business technology news, follow InfoWorld.com on Twitter.