A FLEXIBLE REAL-TIME SCHEDULING ABSTRACTION - DESIGN AND IMPLEMENTATION

An evolution is happening in the way that operating systems support th e real-time requirements of their applications. The need to run real-t ime applications such as multimedia in the same environment as complex non-real-time servers and applications has motivated much interest in restructuring existing operating systems. Many issues related to thre ad scheduling and synchronization have been investigated. However, lit tle consideration has been given to the flexibility and modularity req uired in the support of application-level scheduling needs, although i t is well known that application requirements are diverse. In this pap er, we describe a real-time scheduling abstraction which provides modu larity and flexibility to the scheduling support of operating systems. Our design has been implemented using the Mach 3.0 kernel and a local ly developed multiprocessor kernel (the r-kernel) as development platf orms. (C) 1997 by John Wiley & Sons, Ltd.