{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/125706"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/125706","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Exascale finite/spectral element simulations","abstract":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2026-08-01","abstract_html":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2026-08-01","abstract_has_math":false,"creators":["Ratnayaka Mudiyanselage, Thilina Bandara"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Computer Science","degree_department":null,"school":null,"contributors":["Fischer, Paul","Olson, Luke","Kloeckner, Andreas","Rowe, Kris"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-07-09","date_published":"2024-07-09","updated_at":"2026-07-22T22:25:02Z","subjects":["Hpc","Gpu","Mpi","Graph Partitioning","Schwarz Methods","Coarse-grid","P-multigrid","Loopy","Programming Models","Clang","Exascale Computing"],"languages":["en","eng"],"rights":["Copyright 2024 Thilina Ratnayaka"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/125706","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Fischer, Paul","Olson, Luke","Kloeckner, Andreas","Rowe, Kris"]},{"key":"dc:creator","label":"Author","values":["Ratnayaka Mudiyanselage, Thilina Bandara"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2024-07-09","2024-08"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Computer Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Hpc","Gpu","Mpi","Graph Partitioning","Schwarz Methods","Coarse-grid","P-multigrid","Loopy","Programming Models","Clang","Exascale Computing"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2024 Thilina Ratnayaka"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/125706"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2026-08-01","The student, Thilina Ratnayaka Mudiyanselage, accepted the attached license on 2024-07-09 at 12:16.","The student, Thilina Ratnayaka Mudiyanselage, submitted this Dissertation for approval on 2024-07-09 at 12:17.","This Dissertation was approved for publication on 2024-07-09 at 14:48.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21005 on 2025-02-04 at 21:16:31","In this thesis, we present contributions by author and his collaborators to improve the efficiency of high-order spectral/finite element simulations (SEM/FEM) on state-of-the-art exascale and pre-exascale supercomputers with general purpose graphics processing units (GPUs). We briefly discuss the exascale computing landscape and the challenges involved in running high-order SEM/FEM simulations on these machines. Then we present contributions which span four important aspects of high-order SEM/FEM simulations. Firstly, we present representative benchmarks for SEM/FEM applications and use those to benchmark new GPU based exascale systems in order to understand their scalability characteristics. Secondly, we present a parallel partitioner suitable for the exascale era that is characterized by large local problem sizes. Our partitioner is based on recursive spectral bisection and is able to partition a mesh in parallel while preserving load balance and reducing mes- sage volume between partitions. Thirdly, we address one of the main bottlenecks in the SEM/FEM simulations: the coarse-grid solve of the p−Multigrid preconditioner used for solving the pressure Poisson equation. We introduce a novel two-level Schwarz based coarse solver which has the potential to scale well on the exascale machines due to its low communication and increased parallelism. Finally, we present a domain specific compiler framework to improve the productivity of the application engineers who use GPU-based supercomputers by reusing domain specific optimization patterns."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Exascale finite/spectral element simulations"]}]}],"canonical_facts":{"dc:contributor":["Fischer, Paul","Olson, Luke","Kloeckner, Andreas","Rowe, Kris"],"dc:creator":["Ratnayaka Mudiyanselage, Thilina Bandara"],"dc:date":["2024-07-09","2024-08"],"dc:description":["Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2026-08-01","The student, Thilina Ratnayaka Mudiyanselage, accepted the attached license on 2024-07-09 at 12:16.","The student, Thilina Ratnayaka Mudiyanselage, submitted this Dissertation for approval on 2024-07-09 at 12:17.","This Dissertation was approved for publication on 2024-07-09 at 14:48.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21005 on 2025-02-04 at 21:16:31","In this thesis, we present contributions by author and his collaborators to improve the efficiency of high-order spectral/finite element simulations (SEM/FEM) on state-of-the-art exascale and pre-exascale supercomputers with general purpose graphics processing units (GPUs). We briefly discuss the exascale computing landscape and the challenges involved in running high-order SEM/FEM simulations on these machines. Then we present contributions which span four important aspects of high-order SEM/FEM simulations. Firstly, we present representative benchmarks for SEM/FEM applications and use those to benchmark new GPU based exascale systems in order to understand their scalability characteristics. Secondly, we present a parallel partitioner suitable for the exascale era that is characterized by large local problem sizes. Our partitioner is based on recursive spectral bisection and is able to partition a mesh in parallel while preserving load balance and reducing mes- sage volume between partitions. Thirdly, we address one of the main bottlenecks in the SEM/FEM simulations: the coarse-grid solve of the p−Multigrid preconditioner used for solving the pressure Poisson equation. We introduce a novel two-level Schwarz based coarse solver which has the potential to scale well on the exascale machines due to its low communication and increased parallelism. Finally, we present a domain specific compiler framework to improve the productivity of the application engineers who use GPU-based supercomputers by reusing domain specific optimization patterns."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/125706"],"dc:language":["en","eng"],"dc:rights":["Copyright 2024 Thilina Ratnayaka"],"dc:subject":["Hpc","Gpu","Mpi","Graph Partitioning","Schwarz Methods","Coarse-grid","P-multigrid","Loopy","Programming Models","Clang","Exascale Computing"],"dc:title":["Exascale finite/spectral element simulations"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Computer Science"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:02Z"}