Feature discussion: xhyve support

[tianon]

Since xhyve can't directly boot an ISO (from anything I can find), I'm thinking that perhaps it would be useful for us to release a boot2docker-xhyve.tar.xz (possibly .tar.gz instead since Go has better support for .gz...) which contains the kernel, initrd, and a cmdline file with boot arguments.

However, it does seem a little bit strange to make xhyve an explicit variant when all that's different is going to be VARIANT_ID and VARIANT in os-release and the fact that it's not released as an ISO.

I'm also not certain if we need nasty sleep hacks in our formatting script like in boot2docker/boot2docker#981, given that we're using the full Debian-provided tools for partitioning.

[SvenDowideit]

I already build the initrd.img and vmlinuz64 in my Makefile so that I can quickly test using a cmdline qemu - so ya.

for my usage, I'm exploring building totally different kernel options for each vm platform - so from my POV, the xhyve variant would eventually have more differences than just non-iso format.

[jakirkham]

Instead of using boot2docker-xhyve.tar.gz maybe it would be good to use boot2docker-xhyve.tar.bz2; since, it sounds like you are planning to include binary data anyways. It looks like this is included in compress, as well. ( https://golang.org/pkg/compress/bzip2/ )