Mapping skeleton workflows onto heterogeneous platforms Anne Benoit - PowerPoint PPT Presentation

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Mapping skeleton workflows onto heterogeneous platforms Anne Benoit and Yves Robert GRAAL team, LIP ´ Ecole Normale Sup´ erieure de Lyon June 2007 Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 1/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Introduction and motivation Mapping applications onto parallel platforms Difficult challenge Heterogeneous clusters, fully heterogeneous platforms Even more difficult! Structured programming approach Easier to program (deadlocks, process starvation) Range of well-known paradigms (pipeline, farm) Algorithmic skeleton: help for mapping Mapping skeletons (pipeline, fork) onto heterogeneous platforms Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 2/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Rule of the game Map each pipeline stage on a single processor (extended later) Goal: minimize execution time (extended later) Several mapping strategies S 1 S 2 S k S n ... ... The pipeline application Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 3/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Rule of the game Map each pipeline stage on a single processor (extended later) Goal: minimize execution time (extended later) Several mapping strategies S 1 S 2 S k S n ... ... The pipeline application Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 3/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Rule of the game Map each pipeline stage on a single processor (extended later) Goal: minimize execution time (extended later) Several mapping strategies S 1 S 2 S k S n ... ... One-to-one Mapping Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 3/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Rule of the game Map each pipeline stage on a single processor (extended later) Goal: minimize execution time (extended later) Several mapping strategies S 1 S 2 S k S n ... ... Interval Mapping Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 3/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Rule of the game Map each pipeline stage on a single processor (extended later) Goal: minimize execution time (extended later) Several mapping strategies S 1 S 2 S k S n ... ... General Mapping Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 3/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Major contributions Theory Formal approach to the problem, definition of replication and data-parallelism Problem complexity for several cases Integer linear program for exact resolution Practice Heuristics for Interval Mapping on clusters Experiments to compare heuristics and evaluate their absolute performance Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 4/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Major contributions Theory Formal approach to the problem, definition of replication and data-parallelism Problem complexity for several cases Integer linear program for exact resolution Practice Heuristics for Interval Mapping on clusters Experiments to compare heuristics and evaluate their absolute performance Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 4/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Outline Framework 1 Working out an example 2 Part 1 - Communications, monolithic stages, mono-criterion 3 Part 2 - Simpler model with no communications, but with 4 replication/DP and bi-criteria Conclusion 5 Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 5/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion Outline Framework 1 Working out an example 2 Part 1 - Communications, monolithic stages, mono-criterion 3 Part 2 - Simpler model with no communications, but with 4 replication/DP and bi-criteria Conclusion 5 Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 6/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion The application: pipeline graphs δ 0 δ 1 δ k − 1 δ k δ n S 1 S 2 S k S n ... ... w 1 w 2 w k w n n stages S k , 1 ≤ k ≤ n S k : receives input of size δ k − 1 from S k − 1 performs w k computations outputs data of size δ k to S k +1 Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 7/ 44

Introduction Framework Example Part 1 - Coms, No Rep/DP, 1c Part 2 - No coms, Rep/DP, 2c Conclusion The application: fork graphs δ − 1 w 0 S 0 δ 0 δ 0 δ 0 δ 0 S 1 S 2 S k S n w 1 w 2 w k w n ... ... δ 1 δ 2 δ k δ n n + 1 stages S k , 0 ≤ k ≤ n S 0 : root stage S 1 to S n : independent stages A data-set goes through stage S 0 , then it can be executed simultaneously for all other stages Anne.Benoit@ens-lyon.fr Cetraro, June 07 Mapping skeleton workflows WS’07 8/ 44