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  1. 1. Implementation Profiling Process of AllPathsLG was performed for the following unpaired data sets using AllPathsLG-46513 including the memusage script by Liu Yongchao (University of Mainz) on BioU and job accounting scripts on Blacklight. Abstract Next Generation Sequencers (NGS) provide high throughput by parallelizing the sequencing process, and producing millions of sequences in a relatively short amount of time. Because NGS is still relatively new, the methods to assemble data have not been fully explored from an optimization perspective. One such assembler is ALLPATHS-LG, whose optimization profiling is the focus of this poster. In order to carry out the profiling tasks, the CPU and memory usage of each step of the program was analyzed using profilers. The profiling process highlighted which steps were taking the most amount of time, and if possible, each step was optimized accordingly. In order to maximize the efficiency and throughput of the program as a whole, steps with the highest amount of I/O, memory, and CPU time were given the most priority, in order to decrease the amount of time for sequence assembly. Background NGS data output has increased at a rate that outpaces Moore’s law, more than doubling each year since it was invented. In 2007, a single sequencing run could produce a maximum of around one gigabase (Gb) of data. By 2011, that rate has nearly reached a terabase (Tb) of data in a single sequencing run—nearly a 1000× increase in four years. With the ability to rapidly generate large volumes of sequencing data, NGS enables researchers to move quickly from an idea to full data sets in a matter of hours or days. Researchers can now sequence more than five human genomes in a single run, producing data in roughly one week, for a reagent cost of less than $5,000 per genome. This optimization of the sequence alignment code, will help cut both time and cost. Analysis Profiling the code on BioU and Blacklight resulted in the identification of seven routines that consume large amounts of CPU time as shown on the graphs. Additionally, these modules have the most I/O associated with them which makes the good candidates for optimization. In order to maximize the optimization, different factors such as elapsed time, memory used, and I/O have to be taken into account. Modules such as FindErrors, AlignReads, and CommonPather are good candidates for optimization. Acknowledgements References  Sante Gnerre, Iain MacCallum, Dariusz Przybylski, Filipe J. Ribeiro, Joshua N. Burton, Bruce J. Walker, Ted Sharpe, Giles Hall, Terrance P. Shea, Sean Sykes, Aaron M. Berlin, Daniel Aird, Maura Costello, Riza Daza, Louise Williams, Robert Nicol, Andreas Gnirke, Chad Nusbaum, Eric S. Lander, and David B. Jaffe. High-quality draft assemblies of mammalian genomes from massively parallel sequence data. PNAS [Online] 2010.  Gperftools. oglePerformanceTools>. June 13,2013  This research was supported by the NIH Grants T36-GM-095335 and 2-P41-RR06  Alexander J. Ropelewski  Dr. Bienvenido Velez  Pittsburgh Super Computing Center Parallel Benchmarking and Performance Profiling of de novo Genome Assembly Algorithms Appropriate for NGS Data Jan Salomon1, Alex Ropelewski2; Bienvenido Velez3 1Electrical and Computer Engineering Department, University of Puerto Rico, Mayaguez 2Pittsburgh Supercomputing Center, Pittsburgh, PA BioU Results Species Number of Fragment Reads Fragment Read Length Number of Jump Reads Jump Read Length Bifidobacterium bifidum NCIMB 41171 1096991 101 1193262 93 Neisseria gonorrhoeae FA19 1748810 101 902879 101 Coprobacillus sp. D6 1271918 101 1775443 101 Enterococcus casseliflavus 899205 1588485 101 1265671 101 Eubacterium sp. 3_1_31 826347 93 828826 93 0 500 1000 1500 2000 2500 3000 PostPatcher TagCircularScaffolds KPatch UnibaseCopyNumber3 CleanCorrectedReads CleanAssembly CloseUnipathGaps RebuildAssemblyFiles FixLocal CommonPather FindErrors Other (<97) UnipathPatcher LocalizeReadsLG AlignReads Time Taken (seconds) AllPathsLGModule Combined Elapsed Time Per Step 0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 ShaveUnipathGraph UnipathPatcher CloseUnipathGaps RemoveDodgyReads FixLocal CleanCorrectedReads MergeNeighborhoods1 AlignReads FindErrors UnibaseCopyNumber3 LocalizeReadsLG Other (<3.8MB) CommonPather Memory Used (MB) AllPathsLGModule Combined VMRSS(MB) Blacklight Results Blacklight I/O Profiling Results 0 50000 100000 150000 200000 250000 300000 350000 400000 450000 500000 SamplePairedRea UnipathPatcher FixSomeIndels MergeNeighborho FixLocal RemoveHighCNAli ShaveUnipathGra KPatch AlignReads CleanCorrectedR UnibaseCopyNumb RecoverUnipaths LocalizeReadsLG FindErrors CommonPather Other (<54000) Size (MB) AllPathsLGModule Logical I/O Reads 0 100000 200000 300000 400000 500000 600000 700000 800000 SamplePairedRea RemoveHighCNAli FixSomeIndels KPatch MergeNeighborho UnipathPatcher ShaveUnipathGra AlignReads CleanCorrectedR RecoverUnipaths FixLocal LocalizeReadsLG FindErrors UnibaseCopyNumb CommonPather Other (<83000) Size (MB) AllPathsLGModule Logical I/O Written Command Name Characters Read Characters Written AlignReads 110550.85 110970.454 CleanCorrectedR 113703.52 114114.204 CommonPather 369853.39 372239.993 FindErrors 224893.88 225584.826 FixLocal 66690.56 69286.932 FixSomeIndels 59103.36 60129.073 KPatch 109716.77 109789.758 LocalizeReadsLG 163704.31 164067.357 MergeNeighborho 69287.47 69671.636 Other 881481.07 889387.44 RecoverUnipaths 150995.8 151131.303 RemoveHighCNAli 73932.16 74184.158 SamplePairedRea 53789.79 54281.473 ShaveUnipathGra 83679.33 83973.843 UnibaseCopyNumb 122950.22 124257.897 UnipathPatcher 53471.03 54533.504 Future Work Future work will involve profiling at a finer detailed level than the coarse method described in this poster as well as exploring code optimizations for the most resource intensive modules. 0 200 400 600 800 1000 1200 1400 1600 FixSomeIndels SamplePairedReadStats RemoveDodgyReads ValidateAllPathsInputs MakeScaffoldsLG LocalizeReadsLG RemoveDodgyReads UnipathPatcher CloseUnipathGaps CleanCorrectedReads UnibaseCopyNumber3 CommonPather AlignReads FixLocal FindErrors Other (<110) Time Taken (seconds) AllPathsLGModule Elapsed Time 0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 RemoveHighCNAligns SamplePairedReadStats ErrorCorrectJump FixSomeIndels UnipathPatcher ShaveUnipathGraph FixLocal RemoveDodgyReads CloseUnipathGaps AlignReads CleanCorrectedReads FindErrors UnibaseCopyNumber3 LocalizeReadsLG Other (<2457) CommonPather Memory Used (MB) AllPathsLGModule Memory Used 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% bifido clap19 copro entero eubac Time Taken (percentage) DataSet Percentage of Time Taken of Top 7 Modules AlignReads CleanCorrectedReads CloseUnipathGaps CommonPather FindErrors UnibaseCopyNumber3 UnipathPatcher 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% bifido clap19 copro entero eubac Time Taken (percentage) DataSet Percentage of Time Taken of Top 7 Modules AlignReads CleanCorrectedReads CloseUnipathGaps CommonPather FindErrors UnibaseCopyNumber3 UnipathPatcher