One can only gain by replacing EASY Backfilling: A simple scheduling policies case study

Danilo Carastan-Santos 1 Raphael de Camargo 2 Denis Trystram 3 Salah Zrigui 1, *
* Corresponding author
1 DATAMOVE - Data Aware Large Scale Computing
Inria Grenoble - Rhône-Alpes, LIG - Laboratoire d'Informatique de Grenoble
3 MOAIS - PrograMming and scheduling design fOr Applications in Interactive Simulation
Inria Grenoble - Rhône-Alpes, LIG - Laboratoire d'Informatique de Grenoble
Abstract : High-Performance Computing (HPC) platforms are growing in size and complexity. In order to improve the quality of service of such platforms, researchers are devoting a great amount of effort to devise algorithms and techniques to improve different aspects of performance such as energy consumption, total usage of the platform, and fairness between users. In spite of this, system administrators are always reluctant to deploy state of the art scheduling methods and most of them revert to EASY-backfilling, also known as EASY-FCFS (EASY-First-Come-First-Served). Newer methods frequently are complex and obscure and the simplicity and transparency of EASY are too important to sacrifice. In this work, we used execution logs from five HPC platforms to compare four simple scheduling policies: FCFS, Shortest estimated Processing time First (SPF), Smallest Requested Resources First (SQF), and Smallest estimated Area First (SAF). Using simulations, we performed a thorough analysis of the cumulative results for up to 180 weeks and considered three scheduling objectives: waiting time, slowdown and per-processor slowdown. We also evaluated other effects, such as the relationship between job size and slowdown, the distribution of slowdown values, and the number of backfilled jobs, for each HPC platform and scheduling policy. We conclude that one can only gain by replacing EASY-backfilling with SAF with backfilling, as it offers improvements in performance by up to 80% in the slowdown metric while maintaining the simplicity and the transparency of FCFS. Moreover, SAF reduces the number of jobs with large slowdowns and the inclusion of a simple thresholding mechanism guarantees that no starvation occurs. Finally, we propose SAF as a new benchmark for future scheduling studies.
Complete list of metadatas

Cited literature [33 references]  Display  Hide  Download
Contributor : Salah Zrigui <>
Submitted on : Thursday, August 1, 2019 - 1:06:02 PM
Last modification on : Thursday, September 12, 2019 - 12:05:06 PM


Files produced by the author(s)



Danilo Carastan-Santos, Raphael de Camargo, Denis Trystram, Salah Zrigui. One can only gain by replacing EASY Backfilling: A simple scheduling policies case study. CCGrid 2019 - International Symposium in Cluster, Cloud, and Grid Computing, May 2019, Larnaca, Cyprus. pp.1-10, ⟨10.1109/CCGRID.2019.00010⟩. ⟨hal-02237895⟩



Record views


Files downloads