Running Resource and Precedence Constraints in a Hard Real-time System: A policy

Author(s):  
Luis Gutierrez ◽  
Raul Jacinto ◽  
Julio Martinez ◽  
Jose Barrios
Vestnik MEI ◽  
2018 ◽  
Vol 5 (5) ◽  
pp. 73-78
Author(s):  
Igor В. Fominykh ◽  
◽  
Sergey V. Romanchuk ◽  
Nikolay Р. Alekseev ◽  
◽  
...  

Author(s):  
Diego Pinheiro ◽  
Rawlinson Goncalves ◽  
Eduardo Valentin ◽  
Horacio Oliveira ◽  
Raimundo Barreto

1994 ◽  
Vol 38 ◽  
pp. 215-219
Author(s):  
John M. Winter ◽  
Robert E. Green

Synchrotron white beam transmission topography of GaAs as previously reported by the authors relied on scanning specimen and film synchronously through the incident x-ray beam to record transmission topographic images en film. Sometimes the total dose required for reasonable contrast on film carried with it enough thermal deposition to cause elastic warping of the wafer. To escape these problems, a real time system was assembled. This system included an image intensifier, a solid state camera, a computer board to frame-grab and digitize images, and appropriate image processing software. With this system, a three inch specimen was scanned from edge to edge in one minute. At this scan rate, the incident x-ray beam had to be significantly attenuated to avoid saturating the intensifier output.


Symmetry ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 172 ◽  
Author(s):  
Hoyoun Lee ◽  
Jinkyu Lee

In a real-time system, a series of jobs invoked by each task should finish its execution before its deadline, and EDF (Earliest Deadline First) is one of the most popular scheduling algorithms to meet such timing constraints of a set of given tasks. However, EDF is known to be ineffective in meeting timing constraints for non-preemptive tasks (which disallow any preemption) when the system does not know the future job release patterns of the tasks. In this paper, we develop a scheduling algorithm for a real-time system with a symmetry multiprocessor platform, which requires only limited information about the future job release patterns of a set of non-preemptive tasks, called LCEDF. We then derive its schedulability analysis that provides timing guarantees of the non-preemptive task set on a symmetry multiprocessor platform. Via simulations, we demonstrate the proposed schedulability analysis for LCEDF significantly improves the schedulability performance in meeting timing constraints of a set of non-preemptive tasks up to 20.16%, compared to vanilla non-preemptive EDF.


2013 ◽  
Vol 475-476 ◽  
pp. 1161-1166
Author(s):  
Xu Dong Zhu ◽  
Hui You Chang

This paper puts forward a novel constraint specification. By limitations on the maximum of consecutive miss of deadline and the minimum probability of meeting deadline on the fixed sliding window s×m, the novel constraint specification has three contributions to the research of the weakly hard real-time system constraint specification. Firstly, has configurable flexible parameters which can easily realize all hard real-time, soft real-time and weakly hard real-time only by changing the parameters. Secondly, replacing the "fixed sliding window" with the "any" window, the novel constraint specification not only simplify the calculation of real-time, which will reduce the time consume, but also broaden the application scope such as smoothly scheduling. Moreover, the fixed sliding window is helpful to find a schedulable μ-pattern. Thirdly, the novel constraint specification solves the invalidity of some constraint specification when the first invocation of task is lost or missed. Through analysis and experiments, the results demonstrate that our novel constraint specification outperform previous approaches in both calculation methods and application scopes.


Sign in / Sign up

Export Citation Format

Share Document