An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs

O/S, circa 1993

• Debian, Slackware
• Windows NT 4

1993 Hardware

• Pentium just arrived!
• 16MB of RAM
• ~ 100MB hard drive

How did we use computers

• Almost no multi-tasking
• Personal computers, some SMB servers
• Many application on a node
• Minimal networking
• Maintained by humans, frequent config changes
• Lifespan: years

How do we use computers today

• Servers, appliances
• Lots of networking
• Automated management
• On servers, 1 service per node
• Lifespan can be minutes

Virtualization changed the world

• Hypervisor took over resource managment and containment
• Common drivers
• VM is the new process

The problem with privileges

The problem with containment

while true; mkdir t; cd t; done

• Application resource limits
• Application privileges
• Process centric, not user centric

The problems with packaging

• Debian buzz had 474 packages
• Software projects were split to libraries, docs, development tools/headers to save space
• Dynamic linking to save RAM and ease security upgrades
• Dependency management to prevent conflicts and ommisions

Debian wheezy has ~13k packaged software, CentOS 6 ~2k

But there are 1M projects on Github alone

Maintainers can't keep up

Dynamic linking no longer makes sense

• (almost) impossible to satisfy dependencies
• No RAM or disk space issues anymore
• Single app on node

Omnibus

• Huge all-in-one packages
• No dependencies, everything in the package

The problem with maintenance and configuration

• Gazillion configuration interfaces
• Many control interfaces (e.g. reload)
• No telemetry and monitoring services
• Resource ownership information

The problem with automation

yes | ./install.sh

• O/S built for human control
• Automation support 2nd class
• Packages do too much
• Config file formats

OpenLMI

• System management API
• Local and remote
• Available in Fedora 19

JeOS

• It's all about the Application
• Runtimes do a lot
• No need for users, permissions, scheduling, etc

• Erlang on Xen
• OSv
• CoreOS

Appliances

• High level application APIs
• Application level permissions
• Native cloud integration

Android, IOS, Windows mobile, Firefox OS

Distributed computing

Programming for 128 cores is a lot like programming for 64 core-duo nodes

The Grid

• Aggregation of clusters
• Resource scheduler, job management
• Monitoring
• Job containment
• API
• Global file system/storage

Plan 9

• Natively distributed O/S
• Started ~1987, released 1992
• Had many advanced features, still influencing O/S

Mosix (HUJI)

• SSI grid
• Started 1977, linux since 1999
• Live process migration
• Automatic resource management

Welcome to the future

• Orleans (Microsoft)
• Borg/Omega (Google)
• Mesos (Twitter, AirBnB)
• Hadoop YARN (Yahoo)