Issues in the static allocation and scheduling of complex periodic tasks
RTOSS '93 Proceedings of the tenth IEEE workshop on Real-time operating systems and software
The Deferrable Server Algorithm for Enhanced Aperiodic Responsiveness in Hard Real-Time Environments
IEEE Transactions on Computers
Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment
Journal of the ACM (JACM)
Schedulability analysis of periodic and aperiodic tasks with resource constraints
Journal of Systems Architecture: the EUROMICRO Journal - Special issue on real-time systems
Priority Inheritance Protocols: An Approach to Real-Time Synchronization
IEEE Transactions on Computers
Scheduling real-time applications in an open environment
RTSS '97 Proceedings of the 18th IEEE Real-Time Systems Symposium
Integrating Multimedia Applications in Hard Real-Time Systems
RTSS '98 Proceedings of the IEEE Real-Time Systems Symposium
Cooperative Scheduling of Multiple Resources
RTSS '99 Proceedings of the 20th IEEE Real-Time Systems Symposium
Exploiting Precedence Relations in the Schedulability Analysis of Distributed Real-Time Systems
RTSS '99 Proceedings of the 20th IEEE Real-Time Systems Symposium
Aperiodic Servers with Resource Constraints
RTSS '01 Proceedings of the 22nd IEEE Real-Time Systems Symposium
Journal of Systems and Software
IRIS: A New Reclaiming Algorithm for Server-Based Real-Time Systems
RTAS '04 Proceedings of the 10th IEEE Real-Time and Embedded Technology and Applications Symposium
Task Synchronization in Reservation-Based Real-Time Systems
IEEE Transactions on Computers
Resource sharing in behavioral based scheduling
Proceedings of the 2009 ACM symposium on Applied Computing
A genetic based disk scheduling method to decrease makespan and missed tasks
Information Systems
A new real time disk-scheduling method based on GSR algorithm
Journal of Systems and Software
Hardware design of a new genetic based disk scheduling method
Real-Time Systems
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This paper presents the Clearing Fund Protocol, a three layered protocol designed to schedule soft real-time sets of precedence related tasks with shared resources. These sets are processed in an open dynamic environment. Open because new applications may enter the system at any time and dynamic because the schedulability is tested on-line as tasks request admission. Top-down, the three layers are the Clearing Fund, the Bandwidth Inheritance and two versions of the Constant Bandwidth Server algorithms. Bandwidth Inheritance applies a priority inheritance mechanism to the Constant Bandwidth Server. However, a serious drawback is its unfairness. In fact, a task executing in a server can potentially steal the bandwidth of another server without paying any penalty. The main idea of the Clearing Fund Algorithm is to keep track of processor-time debts contracted by lower priority tasks that block higher priority ones and are executed in the higher priority servers by having inherited the higher priority. The proposed algorithm reduces the undesirable effects of those priority inversions because the blocked task can finish its execution in its own server or in the server of the blocking task, whichever has the nearest deadline. If demanded, debts are paid back in that way. Inheritors are therefore debtors. Moreover, at certain instants in time, all existing debts may be waived and the servers are reset making a clear restart of the system. The Clearing Fund Protocol showed definite better performances when evaluated by simulations against Bandwidth Inheritance, the protocol it tries to improve.