Unikernels are specialized, lightweight virtual machines containing only the OS components and libraries required to run a single application. This talk discussed various unikernel implementations like MirageOS, OSv, IncludeOS and Rumprun. It highlighted characteristics like fast boot times, small attack surfaces and potential uses in microservices, networking and IoT. Examples were given of building and running unikernels on different platforms including Linux, KVM and cloud providers.

1. Lightning Talk:
Unikernel Technologies
Michael Bright
Solution Architect

2. What are Unikernels?

3. Specialized applications built with
all, but only, the OS components
they need.
A Unikernel is standalone able to run
directly as a VM (or possibly on BM)
Compile in optional “Library OS”
components such as
- Network stack
- File-system
- Device drivers
What are Unikernels?
Hardware
Hypervisor
OS Kernel
User Processes
Parallel Threads
Language Runtime
Application Binary
Configuration Files
Hardware
Hypervisor
Unikernel Runtime
Application Code
Configuration
A Unikernel application
containing only selected
« Library OS » components
A typical application
Running above a
general purpose OS

4. http://bit.ly/2p4o59J
THE NEW STACK
OCTOBER 24, 2016
Debunking Unikernel Criticisms
Unikernels are unfit for production
January 22, 2016 - by Bryan Cantrill
Hacker News Discussion
January 22, 2016
Contentious !
http://bit.ly/2o0Fxg0
“VMs aren’t heavy, Oses are !”,
Alfred Bratterud, #includeOS

5. Characteristics.
• Fast to boot, very light on resources enabling on-demand services
• Single-user, Single-address space, Single-process for performance and security
• Small attack surface so potentially more secure
Why use Unikernels ?
Still very much a research area, but could be used in
• Cloud micro-services: on-demand immutable services
• NFV (Telco Cloud)
• IoT
• Networking Devices or appliances

6. 2 main families
Unikernel
Implementations

7. Clean-Slate
1. MirageOS (Ocaml)
2. HalVM (Haskell)
3. LING (Erlang)
Unikernel Implementations?
Legacy
1. IncludeOS (C/C++)
2. OSv (Java,Lua,Go)
3. Rumprun (Ruby,Go,Python…)
4. Graphene (C, linux binaries)
5. ClickOS (modular router)
6. Clive (Go)
7. HermitCore (“gcc”)
8. … and more still …
Tools
1. Unik
2. Solo5 / ukvm

8. MirageOS v3 supports more backends inc. kvm & xhyve.
• MirageOS Unikernels – “Library OS” and app - written entirely in Ocaml
• Jitsu project allows on demand “just in time spawning of unikernels”
• The mirage tool creates a build envt for the chosen backend (unix, xen, kvm, …)
MirageOS Unikernels: Clean-slate
Build/run as Linux binary
mirage configure –t unix
make depend
make
./binary
Build/run under kvm
mirage configure –t ukvm
make depend
make
./ukvm-bin unikernel-binary
[Xen incubator project] MirageOS v3 – Feb 2017

9. Let’s build/run a unikernel on:
- Unix (Linux)
- To run locally
- Ukvm
- To run under ukvm locally
- To run in the cloud
Demo: MirageOS
Clean-slate Unikernel

10. [Cloudius Systems] Osv 0.24 – Oct 2015
• Execute single app on any hypervisor
• Capstan tool builds for VirtualBox, KVM, Xen, VMWare
• Supports many application languages
• Java, C, Lua, Ruby, Go, Node.js, Scala, …
• ZFS snapshots, REST api, cloud-init
Manifesto
• Run existing Linux apps, run them faster
• Boot time ~ exec time (< 1 sec)
• Leverage memory managed platforms (JVM, Go, Lua)
• Stay open
Osv:

11. Demo: OSv
Let’s build/run a unikernel on:
- Unix (Linux)
- To run locally
- VM
- To run under VM locally
- To run in the cloud

12. [HiOA. Oslo] IncludeOS v0.10 - Mar 2017
IncludeOS
A minimal unikernel for running C++ services in
the cloud.
Currently supports – VirtualBox, KVM
(whence GCE, OpenStack)
• Single threaded by default
• Written in C++
• Async i/o only for now
• Potentially for baremetal also

13. Demo: IncludeOS
Let’s build/run a unikernel on:
- Unix (Linux)
- To run locally
- VM
- To run under VM locally
- To run in the cloud

14. [NetBSD] No releases, but very active
Runs existing unmodified POSIX software as a unikernel.
Many packages available (apache2, nginx, haproxy, redis, mysql, …)
Supports bare hardware and hypervisors such as Xen and KVM.
Based on rump kernels which provide many NetBSD OS components
such as drivers, file systems, POSIX system calls, TCP/IP stack
Extensive language support:
• C/C++, Erlang, Go, Java, Node.js, Python, Ruby, Rust …
Rumprun:

15. Demo: Rumprun
Let’s build/run a unikernel on:
- Unix (Linux)
- To run locally
- VM
- To run under VM locally
- To run in the cloud

16. [??] V0.2.14 – Aug 1, 2016
Unikernels for the cloud built on the V8 JavaScript engine.
Bundled up with an application and deployed as a lightweight and
immutable VM image.
Uses event-driven and non-blocking I/O model inspired by Node.js.
At the moment KVM is the only supported hypervisor.
Runtime.js:

17. Demo: Runtime.js
Let’s build/run a unikernel on:
- Unix (Linux)
- To run locally
- VM
- To run under VM locally
- To run in the cloud

18. We can
- build a Unikernel online
- Rumprun, IncludeOS or OSv
- Deploy online
- Pull the image and run locally
- virgo pull myapp
- virgo run myapp
Demo: DeferPanic
Unikernel IaaS

19. Here’s my take
• Still research projects but many early adopters
• More test and production deployments
• Better tooling through tools like Docker, Unik, OSv Capstan
• Increased collaboration across projects
• Increased Hypervisor support
• Different Unikernel technologies for different uses
• Clean-slate for lightest, most secure needs – very specialized
• Hybrid architectures with Unikernels and Containers
• Legacy Unikernels for higher performance from existing apps, e.g. HPC
What’s next ?

20. Thank You!
Questions?
@docker
#dockercon

21. Unikernels: General Resources
URL
Unikernel.org https://unikernel.org
Wikipedia https://en.wikipedia.org/Unikernels
My Scoop.IT https://scoop.it/Unikernels
LinkedIn Group https://www.linkedin.com/groups/8469145
YouTube Playlist http://bit.ly/2mJ6nfw

22. Unikernels: Project Resources
Website GitHub
MirageOS mirage.io mirage/mirage
HalVM galois.com galoisInc/HaLVM
LING erlangonxen.org cloudozer/ling
IncludeOS includeos.org hioa-ca/IncludeOS
Rumprun rumpkernel.org rumpkernel/rumprun
Osv osv.io cloudius-systems/osv

23. Unikernels: Project Resources
Website GitHub
Runtime.js runtimejs.org runtimejs/runtime
Clive lsub.org/ls/clive.html git.lsub.org/clive
ClickOS cnp.neclab.eu/clickos kohler/click
Unik emc-advanced-dev/unik
Deferpanic IaaS deferpanic.net deferpanic/virgo