1 Artificial Evolution: From Clusters to GRID Erol Şahin Cevat Şener Dept. of Computer Engineering Middle East Technical University Ankara

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 2 Darwinian Evolution A population consists of a variety of individuals. The traits of individuals are determined by their genomes. Fitter individuals tend to produce more-than-average off-springs. Off-springs are generated by a recombination of the genomes of the fitter individuals.

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 3 Artificial Evolution Generate a population of solutions. Evaluate the quality of each solution using a pre-defined “fitness function”. Use the fitter solutions to generate more- than-average new solutions. New solutions generated by a recombination of fitter solutions.

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 4 EVOLUTION Environment Individual Fitness PROBLEM SOLVING Problem Candidate Solution Quality Quality  chance for seeding new solutions Fitness  chances for survival and reproduction The metaphor Slide taken from Eiben and Smith’s presentation.

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 5 Evolutionary robotics Challenge: How to design a controller that would make the robot to perform a desired task? –Manual controller design is often difficult/impossible –Realistic simulators are used to evaluate different controller alternatives.

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 6 Evolutionary robotics Sensor data Actuator outputs Convert to controller parameters Use the controller in robots Controller Chromosome

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 7 Evolving controllers Generation n Chrom.1: Chrom.2: Generation n+1 Select Reproduce Mutate Chrom.1: Chrom.2: Population n Population n+1

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 8 Physics Based Simulation Pros –Faster and more reliable than experimentation with real robots –Realistic Cons –High processing demand!

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 9 Single Machine Limitations Computation required: –Solving Ordinary Differential Equations –Increasing complexity with more collisions Time estimates for single computer: –Order of minutes for a single evaluation –For 100 chromosomes and 100 generations Total time > a week on a single machine

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 10 Parallel Evolution System (PES) on a Cluster

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 11 PES Architecture Server: Artificial Evolution Clients: Fitness evaluation PES-C Client Application PES-S Server Application

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 12 PES Communication Model PES Network Adapter PVM Host PES-C PES Network Adapter PVM Host PES-S

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 13 PES-S Architecture Server Application Artificial Evolution Task Manager PES-S Configuration Manager Task generator Best solutions

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 14 PES-C Architecture PES-C Client Application Simulator Fitness Evaluator Task Fitness

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 15 Processor Load Balancing Dynamic simulation Varying number of collisions Varying task complexity Varying processor load Diamonds and Hexagons: tasks Solid lines: Start of new generation

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 16 Fault Tolerance Processor 2 fails Detected at ping at 15 th sec Task restart at 19 th sec Red lines: Ping Blue lines: Generation Numbers: Task index

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 17 Efficiency & Speedup

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 18 Generation Gap for 128 Processors

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 19 Implementing PES on a Grid Two alternatives so far: 1.Porting PES as a whole from Clusters to Grid 2.Submitting only the clients onto Grid

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 20 Porting the whole PES 16 pvm PES-S,PES-C,PES-C,...,PES-C PES-S PES-C pvmd... Grid Engine

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 21 Porting the whole PES Advantage –Easy implementation Disadvantage –Requires that 16 nodes become available at the same time to start running

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 22 Only Clients JobArray: 1:15 PES-C PES-S PES-C... Grid Engine PES-C Task Submission Results

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 23 Only Clients Disadvantage –Communication and synchronization setup between PES-S and Grid Engine is not straightforward Advantage –Performance

Ulusal GRID Çalıştayı, Eylül 2005, Ankara 24 Questions/Comments?