This looks interesting, I'm still holding my breath to see if Joyent are going to bring zfs support to docker though. It looks like they're working on reviving lx branded zones instead which is a bit of a bummer as they are (or were) pretty terrible.
We have put (and are putting) a bunch of work into LX branded zones[1], and are at the point that they are working on an incredibly broad class of apps (64-bit and with on-the-metal performance). A concrete case in point: we recently ran the (amazing!) hundred language quine relay[2] in an LX branded 64-bit Ubuntu 14.04 zone on SmartOS.[3]
As for ZFS support and Docker, it will be via sdc-docker[4], our (emerging) end-point for the Docker Remote API. The progress there has been swift and everything is being done in the open; expect to see something in production from us in this first calendar quarter.
Am I right to assume then that there isn't going to be a SmartOS/SunOS 'docker' client which can understand zfs+zones / replace vmadm/zoneadm? I had planned on looking into writing this when they announced the 'new' pluggable architecture some while ago..
We don't plan to do such a thing, but we would (obviously) be supportive. The challenges for a Docker daemon on SmartOS are several-fold: first, while clearly sympathetic to cross-platform concerns, Docker itself isn't actually (yet) cross-platform, and many Linux-isms were found in putatively generic code. Second, the Docker daemon has a hard dependency on cgo, which is even nastier than Go itself to get working on non-Linux systems. (We did ultimately get cgo working on illumos -- albeit arguably at the cost of the sanity of the engineer who did the work.[1]) Finally, in terms of deploying this into production, we're not about to take third party code from anyone and run it in the global zone on production machines.
So for us, it makes much more sense to implement the Docker Remote API on top of SmartDataCenter, which has the added advantage of virtualizing the concept of a Docker host to be an entire datacenter. But again, we would be supportive of any effort to straight-up port Docker to SmartOS, and we are generally supportive of any container effort that is looking beyond the (mis)design of Linux containers (including the work linked to here for FreeBSD + ZFS).
Consider looking at Warden/Garden as alternative. The main backend currently is for Linux and uses some of the same stuff as Docker. But there's a Windows backend coming too and (hand-wavey gesture here) I imagine this means it was written fairly generically.
