| 1. |
|
|
| 2. |
- Karlsson, Emil, 1990-, et al.
(author)
-
Instance dataset for a multiprocessor scheduling problem with multiple time windows and time lags : Similar instances with large differences in difficulty
- 2022
-
In: Data in Brief. - : Elsevier. - 2352-3409. ; 45
-
Journal article (peer-reviewed)abstract
- The dataset presented in this paper introduces 384 new instances for the feasibility version of a multiprocessor scheduling problem with multiple time windows, positive time lags and exact time lags. The instances are constructed from subproblems in a logic-based Benders decomposition scheme introduced in "Logic-based Benders decomposition with a partial assignment acceleration technique for an avionics scheduling problem" (Karlsson, E., Rönnberg, E., Computers & Operations Research, 2022) [1]. A key aspect of the dataset is that even if two instances are highly similar, the computational performance of solving them with an IBM ILOG CP Optimizer model can be vastly different. There exists for example 47 pairs of instances with the same number of tasks and exact time lags, and the number of positive time lags differs with at most two, where one instance can be solved within 5 minutes and the other instance cannot be solved within 24 hours. Such differences make the instance dataset useful for investigating differences in computational performance of constraint programming solvers. The dataset can also be used to benchmark methods for multiprocessor scheduling. The dataset has been released under the Creative Commons Attribution 4.0 International license and can be used as it is or be adapted.
|
|
| 3. |
- Karlsson, Emil, 1990-, et al.
(author)
-
Logic-based Benders decomposition with a partial assignment acceleration technique for avionics scheduling
- 2022
-
In: Computers & Operations Research. - : Elsevier. - 0305-0548 .- 1873-765X. ; 146
-
Journal article (peer-reviewed)abstract
- Pre-runtime scheduling of large-scale electronic systems, as those in modern aircraft, can be computationally challenging. In this paper, we study a distributed integrated modular avionic system of practical relevance where the scheduling includes to assign communication messages to time slots and to sequence tasks on modules. For this problem, the challenge is the huge number of tasks to be scheduled and the intricate interaction between the communication and task scheduling. We present a method based on Logic-Based Benders Decomposition (LBBD) to solve this problem. In a master problem, formulated as a mixed-integer program, communication messages are assigned to time slots and in a subproblem, formulated as a constraint program, tasks are scheduled.Our LBBD scheme is accelerated by using cut strengthening, a subproblem relaxation, and components for preprocessing and initialisation of the scheme. The cut strengthening is of the kind that systematically investigates subsets of variables to include in the cut by solving additional subproblems. To further enhance the efficiency of the scheme, we propose a new strategy that extends cut strengthening to also try to construct feasible solutions by using information from solving the additional subproblems. Our computational evaluation is based on publicly available instances with up to 2530 messages and 54,731 tasks. It shows that our method outperforms previous methods for the problem with respect to both solution times and RAM usage. A further evaluation of the different components in the method shows that our new acceleration strategy is important to achieve these results.
|
|
