# Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment

@article{Liu1973SchedulingAF, title={Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment}, author={C. L. Liu and James W. Layland}, journal={J. ACM}, year={1973}, volume={20}, pages={46-61} }

The problem of multiprogram scheduling on a single processor is studied from the viewpoint of the characteristics peculiar to the program functions that need guaranteed service. It is shown that an optimum fixed priority scheduler possesses an upper bound to processor utilization which may be as low as 70 percent for large task sets. It is also shown that full processor utilization can be achieved by dynamically assigning priorities on the basis of their current deadlines. A combination of…

## 972 Citations

Multiprocessor scheduling of periodic tasks in a hard real-time environment

- Computer ScienceProceedings Sixth International Parallel Processing Symposium
- 1992

Preemptive scheduling a set of periodic tasks on multiprocessors is studied from the point of view of meeting their service requirements before given deadlines to derive complex algorithms including upper bounds on the number of preemptions.

Feasible processor allocation in a Hard-Real-Time environment

- Computer ScienceReal-Time Systems
- 2006

This article presents scheduling algorithms that guarantee all time constraints and are so easy to implement that they can be used in real-time operating systems.

Portioned static-priority scheduling on multiprocessors

- Computer Science2008 IEEE International Symposium on Parallel and Distributed Processing
- 2008

An efficient real-time scheduling algorithm for multiprocessor platforms that achieves higher system utilizations, in which all tasks meet deadlines, with a small number of preemptions compared to traditional algorithms.

An Optimal Multiprocessor Real-Time Scheduling Algorithm

- Computer ScienceJ. Parallel Distributed Comput.
- 1997

The optimal algorithm is shown to be particularly useful when schedules are built from the integral flow values obtained from the corresponding maximum flow network.

Some algorithms for analysis and synthesis of real-time multiprocessor computing systems

- Computer ScienceProgramming and Computer Software
- 2014

The problem of preemptive scheduling in a real-time multiprocessor computing system with release time/deadline intervals is investigated. Approximate algorithms based on the generalization of a…

Competitive Analysis of Static-Priority Partitioned Scheduling on Uniform Multiprocessors

- Computer Science13th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA 2007)
- 2007

An algorithm is proposed that can schedule all task sets that any other possible algorithm can schedule assuming that the algorithm is given processors that are radic2/radic2-1ap 3.41 times faster.

Global static-priority scheduling of sporadic task systems on multiprocessor platforms

- Computer Science
- 2006

The multiprocessor scheduling of collections of real-time jobs is considered and resource-augmentation bounds are provided that quantify the tightness of these schedulability tests.

Competitive Analysis of Partitioned Scheduling on Uniform Multiprocessors

- Computer Science2007 IEEE International Parallel and Distributed Processing Symposium
- 2007

An algorithm is proposed which can schedule all task sets that any other possible algorithm can schedule assuming that the algorithm is given processors that are three times faster.

Optimal utilization bounds for the fixed-priority scheduling of periodic task systems on identical multiprocessors

- Computer ScienceIEEE Transactions on Computers
- 2004

It is proven that this algorithm is optimal from the perspective of achievable utilization in the sense that no fixed-priority algorithm for scheduling periodic task systems upon identical multiprocessors may have an achievable utilization greater than (m+1)/2.

Semi-partitioned Fixed-Priority Scheduling on Multiprocessors

- Computer Science2009 15th IEEE Real-Time and Embedded Technology and Applications Symposium
- 2009

The algorithm is designed so that a task is qualified to migrate, only if it cannot be assigned to any individual processors, in such a way that it is never returned to the same processor within the same period, once it is migrated from one processor to another processor.

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