Scheduling distributable real-time threads in Tempus middleware
Peng Li, Binoy Ravindran, Hyeonjoong Cho, E. Douglas Jensen · 2004
This paper presents the Tempus real-time mid-dleware, which supports Real-Time CORBA 2.0’s distributable threads (DTs) as an end-to-end pro-gramming abstraction for distributed real-time systems. DTs in Tempus can have time con-straints, including time/utility functions (TUFs), can have resource constraints, including mu-tual exclusion, and can be scheduled according to utility accrual (UA) disciplines. Tempus propa-gates the scheduling parameters of DT’s as they transit objects and hence perhaps node bound-aries. Node-local instances of a UA scheduling algorithm use the propagated parameters to con-struct local schedules and resolve resource depen-dencies for local timeliness optimization, toward approximate, system-wide timeliness optimal-ity. Tempus uses an application-level scheduling framework for node-local TUF/UA schedul-ing on real-time POSIX-compliant operating systems. Our experimental measurements demon-strate the effectiveness of the middleware in scheduling DTs.