Parallel Tasks

Efficient approximation algorithms for scheduling moldable tasks

“…Linear-Speedup Model. An ideal speedup model is linear when p does not exceed a threshold δ j (Drozdowski, 2004): t j,p = t j,1 p where η j,p = p; the workload of T j is independent of p since D j,p = pt j,p = t j,1 . Benoit et al (2022a) propose a 2-approximation algorithm, called LPA-LIST, for failure-prone platforms with additional constraints in the process of executing jobs.…”

“…The problem of scheduling moldable tasks to minimize the makespan is strongly NP-hard when m ≥ 5 (Drozdowski, 2004). There is a long history of study with continuous improvements to the approximation ratio or time complexity.…”

“…However, in many cases, the scheduler can decide this number before the task execution: if this number cannot be changed during the task execution, the task is said to be moldable; otherwise, it is said to be malleable 1 . Moldable tasks are easier to implement and manage than malleable tasks; the latter require additional system support for task migrations and preemptions (Drozdowski, 2004).…”

Fast event-based epidemiological simulations on national scales

“…Alternatively, in simulations where the domain crossing events are deterministic and thus predictable, conservative simulation may be used as it is possible to avoid causal violations altogether (Fujimoto, 1990; Heidelberger and Nicol, 1993). In particular, a parallel scheduler (Drozdowski, 2009) can be used to create an execution order which guarantees causality, as has been previously shown by Nicol and Liu (2002) and Xiao et al (1999), notably with the focus on simulation of telecommunication networks.…”