Packing for the Expedition David Culler

5/25/992 Ongoing Endeavors Millennium: building a large distributed experimental testbed –Berkeley Cluster Software Distribution (v1.0 9/99) »automated configuration & mgmt, rexec, SAN,... Ninja: software platform for scalable, customizable services –fast, direct data transfers PostPC departmental environment –wireless networking, small devices, embedded kiosks –networked services

5/25/993 Tech. Prob: Architecture for Billions of Devices option 1: operating systems design for diverse option n: negotiation architecture option n+1: vast data storage and transfer simple devices => opportunity to design and build interesting simple operating systems! –communication centric –not mgmt of threads and address spaces confluence in the very large and very small –simple and fast

5/25/994 What I’m looking for in an Architecture for Billions of Devices

5/25/995 Software Perspective I want to write a “program” today that will deploy itself across a spectrum of devices that we haven’t yet imagined. –what happens where? –how does it adapt? to what? Much easier to adapt within a framework than to organize from scratch

5/25/996 Simplifying Concepts Reservoirs Flows Self-Checking

5/25/997 Comm = Location independent Access to shared storage resv Key Concepts from Parallel Architecture –hierarchical composition of cache-coherence protocols + consistency models –natural framework for adaptation (pull what you touch) Key Extensions –active elements in the protocol hierarchy –intermittent connection –narrow interface with commitment Pilot --- RMI Proxy --- Ninja Service Prototype –device OS = protocol engine

5/25/998 Flows View data transfers as continuous flows –plumbing as programming model –reservoirs provide slack –trade bandwidth for robustness Natural form of adaptation –ex: faster consumer gets more data –flow equations provide goal, simple error bounds, and react –performance availability Flow units become dominant scheduling entity for device = net + sensor/actuator –device OS = flow regulator Several RIVER prototype for many disks

5/25/999 Self-Checking Not diagnostic self-test Actions should have observable consequences –treat them as goals, check that they are met Example –Printer/Scanner –Switch + Light + Photosensor Configure relationships and derive operations

5/25/9910 Plan Now to One Year –many small device distributed simulation tool –prototype cache data pad –prototype smart-rocks flow OS Three Year –develop / obtain many small well-connected devices –integrate with large infrastructure –production quality SimpleOS »small set of building blocks »formal system for composition –demonstrate easy access to massive data –demonstrate high bandwidth flows through small devices