To: seminaire-gallium-moscova@inria.fr From: Francois.Pottier@inria.fr Subject: SEM - INRIA : Gallium - 22/05/08 - Paris - FR Vous pouvez vous abonner à nos annonces de séminaires http://pauillac.inria.fr/seminaires/ S E M I N A I R E __ / _` _ / / o /| /| __ __ __ __ _ _ / ) __) / / / / / /\/| ----- / |/ | / )(_ / / ) ) ) __) (___/ (_/ (_ (_ / (__/ / | / | (__/ __)(_ (__/ (_/ (_/ I N R I A - Rocquencourt Amphi Turing du bâtiment 1 Jeudi 22 mai, 10h30 --------- Jan Vitek --------- Purdue University ================================================ Programming Models for Concurrency and Real-time ================================================ Modern real-time systems are increasingly large, complex and concurrent programs which must meet stringent performance and predictability requirements. Programming those systems require fundamental advances in programming languages and runtime systems. This talk presents our work on Flexotasks, a programming model for concurrent, real-time systems inspired by stream-processing and concurrent active objects. Some of the key innovations in Flexotasks are that it supports both real-time garbage collection and region-based memory with an ownership type system for static safety. Communication between tasks is performed by channels with a linear type discipline to avoid copy of messages, and by a non-blocking transactional memory facility. We have evaluated our model empirically within two distinct implementations, one based on Purdue's Ovm research virtual machine framework and the other on Websphere, IBM's production real-time virtual machine. We have written a number of small programs, as well as a 30 KLOC avionics collision detector application. We show that Flexotasks are capable of executing periodic threads at 10 KHz with a standard deviation of 1.2us and have performance competitive with hand-coded C programs.