The interactive performance of SLIM: a stateless thin-client architecture Brian K. Schmidt and Monica S. Lam Stanford University J. Duane Northcutt Sun Microsystems Laboratories Introduction Computing environment timeline 1970 s: time-sharing on mainframes 1980 s: networks of workstations => return to time-sharing (total cost improve) Thin-client computing (modern version of the old time-sharing) Plan 9 project ( plan9.bell-labs.com ) X terminals, Win Terms, Java Station, other Display protocol ( X, ICA, RDP) High-level, API-specific protocols Thinnest possible clients are dumb terminals MaxStation (MaxSpeed Corporation, 1024x768 8bit 64Mbps) VNC viewer Introduction (con t) SLIM: a stateless thin-client architecture SLIM: a stateless thin-client architecture (con t) SLIM : Stateless, Low-level Interface Machine Statelessness Low-level interface A fixed-function appliance Contains no software The SLIM architecture and implementation The SLIM protocol Simple pixel encodings for display Keyboard and mouse state messages Simple error recovery Implemented on top of UDP/IP The SLIM architecture and implementation (con t) Console is stateless, dumb frame buffer 100MHz microSPARC IIep and 2MB 24-bit 1280x1024 graphics controller 10/100Mbps ethernet interface Interconnection Fabric (IF) Switched, full-duplex 100Mbps Ethernet Server software Daemons for authentication, remote peripheral management, I/O re-direction Device driver and library interfaces to protocol Evaluation methodology Basic performance of each component Characterization of GUI applications Analysis of sharing s impact on performance Explore limit of capabilities using multimedia applications Image ProcessingAdobe Pthotoshop 3.0 Web BrousingNetscape Communicator 4.02 Word ProcessingAdobe Frame Maker 5.5 PIMPersonal Information Management tools Streaming VideoMPEG-II decoder and live video player 3-D CamesQuake from id Software Performance of SLIM components BenchmarkResult Respnse time over a 100Mbps switched IF550us x11perf/Xmark x11perf/Xmark93 no display data sent on IF7.505 Protocol CommandStartup CostCost per Pixel SET5000ns270ns BITMAP11080ns22ns FILL5000ns2ns COPY5000ns10ns CSCS(16bits/pixel)24000ms205ns CSCS(12bits/pixel)24000ms193ns CSCS(8bits/pixel)24000ms178ns CSCS(5bits/pixel)24000ms150ns Characterization of interactive applicaiotns Benchmarks are commonly used GUI apps Analyze characteristics of human interface Real-life data Include analysis of network component User studies characterize interactive performance 50 people performed normal work with app s Logged protocol commands, resource usage Human Interaction Rates Human input rates