Theodore Tso <tytso@xxxxxxx> writes:
On Oct 11, 2011, at 2:42 AM, Eric W. Biederman wrote:
I am totally in favor of not starting the entire world. But just
like I find it convienient to loopback mount an iso image to see
what is on a disk image. It would be handy to be able to just
download a distro image and play with it, without doing anything
special.
Agreed, but what's wrong with firing up KVM to play with a distro
image? Personally, I don't consider that "doing something special".
Then let me flip this around and give a much more practical use case.
Testing. A very interesting number of cases involve how multiple
machines interact. You can test a lot more logical machines interacting
with containers than you can with vms. And you can test on all the
aritectures and platforms linux supports not just the handful that are
well supported by hardware virtualization.
I admit for a lot of test cases that it makes sense not to use a full
set of userspace daemons. At the same time there is not particularly
good reason to have a design that doesn't allow you to run a full
userspace.