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The Partitioned, Static-Priority Scheduling of Sporadic Real-Time Tasks with Constrained Deadlines on Multiprocessor Platforms [chapter]

Nathan Fisher, Sanjoy Baruah
2006 Lecture Notes in Computer Science  
We consider the partitioned scheduling of sporadic, hard-realtime tasks on a multiprocessor platform with static-priority scheduling policies.  ...  Most previous work on the static-priority scheduling of sporadic tasks upon multiprocessors has assumed implicit deadlines (i.e. a task's relative deadline is equal to its period).  ...  Leung and Whitehead [19] showed that determining the feasibility of a task system under the partitioned paradigm is NP-hard.  ... 
doi:10.1007/11795490_23 fatcat:d5e23aj5pfbupo5dapd5wyunqa

A Survey on Scheduling Approaches for Hard Real-Time Systems

Mehrin Rouhifar, Reza Ravanmehr
2015 International Journal of Computer Applications  
This paper composed of two parts; first part surveyed the basic hard RTS scheduling algorithms that guarantee the on-time completion of the tasks.  ...  Finally, the analysis and evaluation of the mentioned methods are shown based on the schedulability of task sets and efficiency.  ...  Static Algorithms Some of the most important static-priority scheduling algorithms are described as follows:  RM (Rate Monotonic) RM is a preemptive and static priority scheduling algorithm on uniprocessor  ... 
doi:10.5120/ijca2015907656 fatcat:na7u3dgqsjhphl253ecd22jkau

PEARLS: An Integrated Environment for Task Scheduling

Nilam Chand, Bindiya Mansharamani, Rafael Romero, Will Beazley, Stefan Andrei
2007 Ninth International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (SYNASC 2007)  
The scheduling problem answers the question whether a given set of input tasks is schedulable (or feasible).  ...  Moreover, the tool is designed to handle both preemptive as well as non preemptive tasks. Both periodic and sporadic tasks and precedence contraints may also be considered in the input.  ...  INTRODUCTION D ECISION versions of scheduling problems belong to NP and most of them are NP-hard [9] , [8] .  ... 
doi:10.1109/synasc.2007.59 dblp:conf/synasc/ChandMRBA07 fatcat:hksl53fqpfhr7kduztv3bk6geq

Schedulability analysis of a graph-based task model for mixed-criticality systems

Pontus Ekberg, Wang Yi
2015 Real-time systems  
These concern the computational complexity of deciding whether a collection of sporadic tasks are schedulable on a uniprocessor.  ...  The main objective of real-time scheduling theory is to analyze properties of mathematical models that capture the temporal behaviors of such systems.  ...  One of these is the problem of deciding whether a given sporadic task system is feasible on a preemptive uniprocessor.  ... 
doi:10.1007/s11241-015-9225-0 fatcat:cy6d3r3ljbb4lmi26ov2o54tcq

Exact speedup factors and sub-optimality for non-preemptive scheduling

Robert I. Davis, Abhilash Thekkilakattil, Oliver Gettings, Radu Dobrin, Sasikumar Punnekkat, Jian-Jia Chen
2017 Real-time systems  
It is known that neither preemptive, nor non-preemptive fixed priority scheduling dominates the other, in other words, there are task sets that are feasible on a processor of unit speed under FP-P that  ...  Fixed priority scheduling is used in many real-time systems; however, both preemptive and non-preemptive variants (FP-P and FP-NP) are known to be sub-optimal when compared to an optimal uniprocessor scheduling  ...  This paper solves an open problem presented at RTSOPS (Davis et al. 2015b ) and at the Dagstuhl Seminar on Scheduling 16081.  ... 
doi:10.1007/s11241-017-9294-3 fatcat:mfxcx3rju5gsraiqu6nxsqdfs4

Simultaneous Progressing Switching Protocols for Timing Predictable Real-Time Network-on-Chips [article]

Niklas Ueter, Georg von der Brueggen, Jian-Jia Chen, Tulika Mitra, and Vanchinathan Venkataramani
2019 arXiv   pre-print
We demonstrate the analytical dominance of the fixed-priority SP^2 over some of the existing sufficient schedulability analysis for fixed-priority wormhole switched network-on-chips.  ...  Such an all-or-nothing property of the SP^2 relates the scheduling behavior on the network to the uniprocessor self-suspension scheduling problem.  ...  Both of them are based on the schedulability analysis for uniprocessor sporadic real-time tasks under fixed-priority scheduling developed in [17] , [25] .  ... 
arXiv:1909.09457v2 fatcat:gk7ud22uyzgytgeu35262nukxm

How Hard is Partitioning for the Sporadic Task Model?

Nathan Wayne Fisher
2009 2009 International Conference on Parallel Processing Workshops  
Partitioning n independent sporadic real-time tasks among m identical processors is known to be an NP-hard in the strong sense (by transformation from bin-packing).  ...  However, currently only "loose" fundamental limits of approximation (trivially based on the known limits for bin packing and partitioning periodic tasks) are known for partitioning sporadic tasks .  ...  Abstract-Partitioning n independent sporadic real-time tasks among m identical processors is known to be an NP-hard in the strong sense (by transformation from bin-packing).  ... 
doi:10.1109/icppw.2009.32 dblp:conf/icppw/Fisher09 fatcat:4d2bun7ynzb7nliaskrxxyr6fq

The Global Limited Preemptive Earliest Deadline First Feasibility of Sporadic Real-Time Tasks

Abhilash Thekkilakattil, Sanjoy Baruah, Radu Dobrin, Sasikumar Punnekkat
2014 2014 26th Euromicro Conference on Real-Time Systems  
The feasibility of preemptive and non-preemptive scheduling has been well investigated on uniprocessor and multiprocessor platforms under both Fixed Priority Scheduling (FPS) and Earliest Deadline First  ...  Specifically, we derive a sufficient condition that guarantees g-LP-EDF feasibility of sporadic realtime tasks which directly provides a global Non-Preemptive Earliest Deadline First (g-NP-EDF) feasibility  ...  A major part of real-time scheduling theory deals with fully preemptive scheduling of periodic and sporadic realtime tasks on uniprocessor [5] [6] [7] [8] and multiprocessor [9] [10] [11]  ... 
doi:10.1109/ecrts.2014.21 dblp:conf/ecrts/ThekkilakattilBDP14 fatcat:4r6ssqmihfclbitpez3j2h46qy

Comparative Study of Scheduling Algorithms for Real Time Environment

Ishan Khera, Ajay Kakkar
2012 International Journal of Computer Applications  
Scheduling is a technique which makes an arrangement of performing certain tasks at specified period.  ...  The various issues have been presented on which there is still a need to work.  ...  time of sporadic task systems which are fixed priority scheduled on a preemptive uniprocessor.  ... 
doi:10.5120/6233-7797 fatcat:z6nergndrne5zfsok7x4wbgxae

Exact comparison of fixed priority and EDF scheduling based on speedup factors for both pre-emptive and non-pre-emptive paradigms

Robert I. Davis, Alan Burns, Sanjoy Baruah, Thomas Rothvoß, Laurent George, Oliver Gettings
2015 Real-time systems  
In this paper, we derive exact speedup factors for both pre-emptive and non-pre-emptive fixed priority scheduling of arbitrary deadline sporadic task sets.  ...  This paper investigates the relative effectiveness of fixed priority (FP) scheduling in a uniprocessor system compared to Earliest Deadline First (EDF) scheduling.  ...  System model, terminology, and notation In this paper, we consider the scheduling of a set of sporadic tasks (or task set) on a uniprocessor system.  ... 
doi:10.1007/s11241-015-9233-0 fatcat:nk6ia2dng5hnbgftcdnkmn3sza

Genealogy of hard real-time preemptive scheduling algorithms for identical multiprocessors

Dirk Müller, Matthias Werner
2011 Open Computer Science  
AbstractWith the advent of multi-core computer systems, real-time (RT) scheduling on multiprocessors (MPs) is gaining more and more practical relevance.  ...  Basic algorithms developed in the 1970s or earlier are strongly influential on state-of-the-art preemptive hard real-time scheduling algorithms.  ...  Acknowledgments The authors would like to thank Ted Baker for useful comments on a preliminary version of this article.  ... 
doi:10.2478/s13537-011-0023-z fatcat:zbzshcwvivd2pe7xm23o54ux2q

Weakly-hard Real-time Guarantees for Earliest Deadline First Scheduling of Independent Tasks

Zain A. H. Hammadeh, Sophie Quinton, Rolf Ernst
2019 ACM Transactions on Embedded Computing Systems  
In this work, we bound the distribution of deadline-misses for task sets running on uniprocessors using the Earliest Deadline First (EDF) scheduling policy.  ...  The results show the usefulness of this approach for temporarily overloaded systems when EDF scheduling is considered. They also show that EDF is especially well for WHRT tasks.  ...  The system model considers sporadic independent tasks in a uniprocessor system under a fixed-priority scheduling policy.  ... 
doi:10.1145/3356865 fatcat:a2jd6hsfrvda5jtzfgiebjegye

A Comparative Study on Dynamic Scheduling of Real-Time Tasks in Multiprocessor System using Genetic Algorithms

Sri RajPradhan, Sital Sharma, Debanjan Konar, Kalpana Sharma
2015 International Journal of Computer Applications  
This paper proposes a compact study on dynamic real time task scheduling in multiprocessor environment using Genetic Algorithm (GA) which is a typically NP-complete problem.  ...  This paper investigates the various scheduling algorithms and compares the simulation result in terms of fitness value and the percentage of success for scheduling real time tasks.  ...  of NP-hard problem.  ... 
doi:10.5120/21340-4346 fatcat:xpdnvuy2jrakrdxemsedsxdaqm

Dual Priority Scheduling is Not Optimal

Pontus Ekberg, Michael Wagner
2019 Euromicro Conference on Real-Time Systems  
Burns and Wellings conjectured that dual priority scheduling is an optimal scheduling algorithm for synchronous periodic tasks with implicit deadlines on preemptive uniprocessors.  ...  In dual priority scheduling, periodic tasks are executed in a fixed-priority manner, but each job has two phases with different priorities.  ...  This problem is clearly in PSPACE and is also (weakly) NP-hard as it generalizes the ordinary fixed-priority schedulability problem [5] . 4 but where?  ... 
doi:10.4230/lipics.ecrts.2019.14 dblp:conf/ecrts/Ekberg19 fatcat:5bvhktqidvgitbbpaoirg7elxa

Rate-monotonic scheduling for hard-real-time systems

Alan A. Bertossi, Andrea Fusiello
1997 European Journal of Operational Research  
This paper provides a review on deterministic scheduling algorithms for hard-real-time systems, focusing mainly on fixed priority, preemptive scheduling of periodic tasks on a single processor and, in  ...  Issues covered include uniprocessor and multiprocessor systems, periodic and non-periodic tasks, restricted and arbitrary deadlines, fixed and dynamic priorities, independent and synchronised tasks, as  ...  Specifically, the problem of deciding whether an arbitrary task system can be scheduled on one processor was proven to be NP-complete [25] .  ... 
doi:10.1016/s0377-2217(97)83306-1 fatcat:vpqgnmngjffl5oatttf3wn3t64
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