[HAIFUX LECTURE] OSv, a new open-source operating system for virtual machines -- Nadav Har'El

Eli Billauer eli at billauer.co.il
Sat Oct 26 19:38:58 MSD 2013

On Monday, October 28th at 18:30, Haifux will gather to hear a talk by 
Nadav Har'El:

    OSv, a new open-source operating system for virtual machines


These days, most applications running on virtual machines in the cloud 
run on top of Linux. We all love Linux, but as an all-encompassing 
operating system for everything from phones to supercomputers, Linux was 
never really designed for virtual machines; It is big and complex, and 
it offers features (such as multi-user and multi-process) which are 
today made redundant by the hypervisor and slow it down. Linux's APIs 
are many times set in stone by decades of legacy code. All these cost in 
application performance, and make it harder to innovate.

This is why OSv was developed, a new operating system designed to run a 
single application on a virtual machine. As it runs a single application 
there is no need for kernel-userspace isolation, reducing context switch 
costs and unnecessary copying. A design from scratch allowed us to 
experiment with new ideas like lock-free mutexes (solving the 
Lock-Holder Preemption problem that plagues operating systems on virtual 
machines), extremely fast context switches, Van Jacobson's network 
channels and more. Also, OSv is released under the more permissive BSD 
license (not GPL like Linux), is tiny compared to Linux, and takes less 
than one second to boot and start the user's application.

OSv can run ordinary Linux shared objects, such as, for example, an 
unmodified JVM (e.g., OpenJDK) executable, and of course on that you can 
run any application written in Java, JRuby , Clojure, or any other JVM 
language. Even at this early stage of OSv's development, OSv can already 
successfully run several interesting workloads such as Netperf, 
Memcached, Cassandra and SpecJVM - and usually match or even beat 
Linux's performance.

Another refreshing feature of OSv is that is written in C++. It's been 
40 years since Unix was (re)written in C, and the time has come for 
something better. C++ is not about writing super-complex type 
hierarchies (as some people might have you believe). Rather, it allowed 
us to write shorter code with less boiler-plate repetition and less 
chances for bugs. It allowed us to more easily reuse quality code and 
data structures. And using newly standardized C++ features, we were able 
to write safe concurrent code with standard language features instead of 
processor-specific hacks. And all of this with zero performance 
overheads - most of C++'s features, most notably templates, are 
compile-time features which result in no run-time overhead compared to C 

OSv was developed by Cloudius Systems, a small Israeli startup led by 
Dor Laor and Avi Kivity (of KVM fame) but it is an open-source project - 
developed since its inception on github, and released under the BSD 
license. We would like to take this opportunity to invite everyone to 
use OSv, and to help drive its development forward. OSv is a fantastic 
playground for kernel developers, and also for people involved in cloud 
development, devops, and so on. Tell us what your dream VM operating 
system will do, and maybe your dream will come true :-) Maybe you can 
even help us make that dream come true.


We meet in Taub building, room 6. For instructions see:

Attendance is free, and you are all invited!

Future lectures:

25/11/13 Nested Virtualization: Shadow Turtles: Muli Ben-Yehuda


We are always interested in hearing your talks and ideas. If you wish to 
give a talk, hold a discussion, or just plan some event haifux might be 
interested in, please contact us at webmaster at haifux.org

Web: http://www.billauer.co.il

More information about the Haifux-announce mailing list