OSv is a lightweight operating system designed to improve performance and administration for applications deployed in the cloud. Learn about the speed and manageability wins from a brand-new OS that works on your private or public cloud.

1. OSV
Avi Kivity, Don Marti
Cloudius Systems
@CloudiusSystems

2. Typical Cloud Stack
Hardware
Hypervisor
OS
JVM
App Server
Your App
OS
JVM
App Server
Your App
OS
JVM
App Server
Your App

3. Our software stack
congealed into existence.

4. Too Many Layers, Too Little Value
Property/Component
Hardware abstraction
Isolation
Resource virtualization
Backward compatibility
Security
Memory management
I/O stack
Configuration
VMM OS runtime
Duplication

6. Transformed the
enterprise from
physical2virtual
Virtualization
Virtualization 1.0 Virtualization 2.0
Compute node
virtual server
Virtualization 2.0, Massive Scale
Scalability

7. Virtualization 2.0
vServer OS 1.0Architecture
● No Hardware
● No Users
● One app/guest
● Yes Complexity

9. The new Cloud Stack - OSv
Hardware
Hypervisor
Core
App
Server
Your App
Single
Process
Kernel
space only
Linked to
existing
JVMs
App sees
no change
Core
Your App

10. The new Cloud Stack - OSv
Memory Huge pages, Heap vs Sys
I/O Zero copy, full aio, batching
Scheduling Lock free, low latency
Tuning Out of the box, auto
CPU
Low cost ctx, Direct
signals,..

11. Alpha Release
3/2014
Optimized ZFS cache
Dirty page writeback
JVM page table
HV support:
GCE, VMW, VBox
Milestones
Git init
osv,
12/2012
Java hello world,
01/2013
support for
64 vcpu
02/2013
UDP,
03/2013
ZFS support
> 1Gbps netperf,
6/2013
Cassandra
outperforms
Linux,
8/2013
Native REST API
Memcached gain >
70%
1/2014
Cli and web
interface
9/2013
Tomcat,
HAProxy
modules
10/2013
Net channels
JVM ballooning
>47Gbps netperf
2/2014
Image Repository
JVM Read barrier
elimination
DPDK support
More ...

12. Memcached benchmark
Requests/s (higher is better)

13. Integrating the JVM into the kernel
Core
JVM
Application
Server
Your AppDynamic
Heap
Memory
TCP in the
JVM + App
context Fast inter
thread
wakeup

14. JVM Garbage Collection and the
kernel
Application thread (“mutator”)
Garbage collection thread
JVM Object
JVM Object
ref

15. JVM Garbage Collection
Application thread (“mutator”)
Garbage collection thread
JVM Object
JVM Object
JVM Object
ref
change

16. JVM Garbage Collection
Application thread (“mutator”)
Garbage collection thread
JVM Object
JVM Object
JVM Object
ref
scan
change

17. JVM Garbage Collection
Application thread (“mutator”)
Garbage collection thread
JVM Object
JVM Object
JVM Object
ref
scan
write
change
card table
read

18. JVM Garbage Collection
Application thread (“mutator”)
Garbage collection thread
JVM Object
JVM Object
JVM Object
ref
scan
change
page table
read
hardware update

19. Van Jacobson == TCP/IP
Common kernel network stack
Leads to servo-loop:

20. Van Jacobson == TCP/IP
Net Channel design:

21. Dynamic heap, sharing is good
JVM Memory System
memory
Lend
memory

22. OS that doesn’t get in the way
4 VMs per sys
admin ratio
http://www.computerworld.com.au/article/352635/there_best_practice_server_system_administrator_ratio_/
NO Tuning
NO State
NO Patching

23. Virtualization 2.0: Stateless servers

24. REST API definition use Swagger
REST api for *any* action

25. Performance and tracing

26. Porting a JVM application to OSV
1. Done*
* well, unless the application fork()s

27. Porting a C application to OSV
1. Must be a single-process application
2. May not fork() or exec()
3. Rebuild as a shared object (.so)
4. Other API limitations apply*
* Post to the list, and missing items are usually added quickly.

28. ● JVM-based application
○ No effort
● Traditional C/C++ application
○ More effort
● Virtio-app
○ NFV - highest gain
Different customization levels

29. ● First OS to be written in C++11
● Interrupt handler using lambda function:
_msi.easy_register({
{ 0, [&] { _rxq.vqueue->disable_interrupts(); },
poll_task},
{ 1, [&] { _txq.vqueue->disable_interrupts(); }, nullptr }
});
OSv == Cool

30. So what about
containers?

31. Capstan demo

32. ● Docker is awesome! Low overhead!
○ Small artifacts
○ Fast deployment
○ Fast startup (container start, not OS boot)
● Docker is awesome! Easy builds!
○ Simple configuration file
○ Minimal additional work on top of application build
Docker is awesome

33. Containers under the hood
● Hypervisors are awesome too!
○ Live migration (load balance, hardware maint)
○ Multiple kernel versions available
● Running VMs everywhere is awesome!
○ Public cloud, private cloud, existing hypervisor...
● Security is awesome!
○ Container attack surface is full kernel interface.
○ Hypervisor attack surface is small.
● Sometimes a hypervisor is already there
(private and public clouds)
Hypervisors are awesome

34. Everything is awesome
What if we could have advantages of Docker
without limitations of containers?
● Fast boot, fast provisioning
● High performance
● Tiny footprint
● Virtualized
○ Live migration
○ Elasticity
○ MMU access

35. Capstan
● Check out a base image
● Build application
● Create complete run-anywhere VM
○ No Capstan needed in production
● 12-20MB and 3 seconds of overhead
● All driven by one simple config file
● Low overhead of containers with
deployment flexibility of a VM image.

36. Let’s Collaborate

37. http://osv.io
https://github.com/cloudius-systems/osv
@CloudiusSystems
osv-dev@googlegroups.com
OSv
@Cloudius

38. Backup slides

39. Virtualization 2.0, Dev/Ops

40. Virtualization 2.0, agility!
Rolling upgrade
within seconds and
a fall back option

41. Cloudius Systems, OS Comparison
Feature/Property
Good for:
Typical workload
kernel vs app
API, compatibility
# Config files
Tuning
Upgrade/state
OSv
Machete:
Cloud/Virtualization
Single app * VMs
Cooperation
JVM, POSIX
0
Auto
Stateless, just boots
JVM support
Lines of code
License
Tailored GC/STW
solution
Fewer
BSD
Traditional OS
Swiss knife: anything
goes
Multiple apps/users,
utilities, anything
distrust
Any, but
versions/releases..
1000
Manual, requires
certifications
Complex, needs
snapshots, hope..
Yet another app
Gazillion
GPL / proprietary

42. Be the best OS
powering virtual machines
in the cloud
Mission statement
Hardware
Hypervisor
OSv
Your App
Hardware
Hypervisor
OSv
+ Jazz JVM
Your App
Hardware
Hypervisor
OSv
+ Jazz JVM
Hardware
Hypervisor
OSv
Hardware
Hypervisor
OSv
+ Jazz JVM
Your App

43. Application upload

44. ● Going idle is much more expensive on
virtual machines
● So are inter-processor interrupts - IPIs
● Combine the two:
○ Before going idle, announce it via shared memory
○ Delay going idle
○ In the meanwhile, poll for wakeup requests from
other processors
● Result: wakeups are faster, both for the
processor waking, and for the wakee
Idle-time polling

45. OSv
applicable for
Virtualization
Application server
Virtual appliance
PaaS
Cloud
Vendors

46. Plan
1. Open Source Launch - Done
2. Harden Virtual Appliances - Doing
3. Q4 2014 GA by Cloud vendors -
Doing
4. OEM (cloud/appliance), Enterprise