Motivated by modern parallel computing applications, we consider the problem of scheduling parallel-task jobs with heterogeneous resource requirements in a cluster of machines. Each job consists of a set of tasks that can be processed in parallel; however, the job is considered completed only when all its tasks finish their processing, which we refer to as the synchronization constraint. Furthermore, assignment of tasks to machines is subject to placement constraints, that is, each task can be processed only on a subset of machines, and processing times can also be machine dependent. Once a task is scheduled on a machine, it requires a certain amount of resource from that machine for the duration of its processing. A machine can process (pack) multiple tasks at the same time; however, the cumulative resource requirement of the tasks should not exceed the machine’s capacity. Our objective is to minimize the weighted average of the jobs’ completion times. The problem, subject to synchronization, packing, and placement constraints, is NP-hard, and prior theoretical results only concern much simpler models. For the case that migration of tasks among the placement-feasible machines is allowed, we propose a preemptive algorithm with an approximation ratio of [Formula: see text]. In the special case that only one machine can process each task, we design an algorithm with an improved approximation ratio of four. Finally, in the case that migrations (and preemptions) are not allowed, we design an algorithm with an approximation ratio of 24. Our algorithms use a combination of linear program relaxation and greedy packing techniques. We present extensive simulation results, using a real traffic trace, that demonstrate that our algorithms yield significant gains over the prior approaches.
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A Truthful Mechanism for Interval Scheduling
Motivated by cloud computing, we study a market-based approach for job scheduling on multiple machines where users have hard deadlines and prefer earlier completion times. In our model, completing a job provides a benefit equal to its present value, i.e., the value discounted to the time when the job finishes. Users submit job requirements to the cloud provider who non-preemptively schedules jobs to maximize the social welfare, i.e., the sum of present values of completed jobs. Using a simple and fast greedy algorithm, we obtain a 1+s/(s−1) approximation to the optimal schedule, where s>1 is the minimum ratio of a job’s deadline to processing time. Building on our approximation algorithm, we construct a pricing rule to incentivize users to truthfully report all job requirements.
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- Award ID(s):
- 1755619
- NSF-PAR ID:
- 10083881
- Date Published:
- Journal Name:
- Lecture notes in computer science
- Volume:
- 11059
- ISSN:
- 0302-9743
- Page Range / eLocation ID:
- 100 - 112
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1007/978-3-319-99660-8_10
