UCIFF: Unified Cluster Assignment Instruction Scheduling and Fast Frequency Selection for Heterogeneous Clustered VLIW Cores

  • Vasileios Porpodas
  • Marcelo Cintra
Conference paper

DOI: 10.1007/978-3-642-37658-0_9

Part of the Lecture Notes in Computer Science book series (LNCS, volume 7760)
Cite this paper as:
Porpodas V., Cintra M. (2013) UCIFF: Unified Cluster Assignment Instruction Scheduling and Fast Frequency Selection for Heterogeneous Clustered VLIW Cores. In: Kasahara H., Kimura K. (eds) Languages and Compilers for Parallel Computing. LCPC 2012. Lecture Notes in Computer Science, vol 7760. Springer, Berlin, Heidelberg

Abstract

Clustered VLIW processors are scalable wide-issue statically scheduled processors. Their design is based on physically partitioning the otherwise shared hardware resources, a design which leads to both high performance and low energy consumption. In traditional clustered VLIW processors, all clusters operate at the same frequency. Heterogeneous clustered VLIW processors however, support dynamic voltage and frequency scaling (DVFS) independently per cluster. Effectively controlling DVFS, to selectively decrease the frequency of clusters with a lot of slack in their schedule, can lead to significant energy savings.

In this paper we propose UCIFF, a new scheduling algorithm for heterogeneous clustered VLIW processors with software DVFS control, that performs cluster assignment, instruction scheduling and fast frequency selection simultaneously, all in a single compiler pass. The proposed algorithm solves the phase ordering problem between frequency selection and scheduling, present in existing algorithms. We compared the quality of the generated code, using both performance and energy-related metrics, against that of the current state-of-the-art and an optimal scheduler. The results show that UCIFF produces better code than the state-of-the-art, very close to the optimal across the mediabench2 benchmarks, while keeping the algorithmic complexity low.

Keywords

clustered VLIW heterogeneous DVFS scheduling phase-ordering 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Vasileios Porpodas
    • 1
  • Marcelo Cintra
    • 1
  1. 1.School of InformaticsUniversity of EdinburghUK

Personalised recommendations