Optimizing existing large codebase 4 Measuare Mo6en世Mem threads fo Overall strategy First measure o understand where time is spent o understand the main limitations Then attack these limitations ●modernize the code o optimizing memory handling o optimizing parallelism optimizing low level code 5/57 S.Ponce-CERNOptimizing existing large codebase 5 / 57 S. Ponce - CERN Measure Modernize Mem threads low level c/c Overall strategy First measure ! understand where time is spent understand the main limitations Then attack these limitations modernize the code optimizing memory handling optimizing parallelism optimizing low level code