Performance of OSCAR Multigrain Parallelizing Compiler on SMP Servers

Abstract

This paper describes performance of OSCAR multigrain parallelizing compiler on various SMP servers, such as IBM pSeries 690, Sun Fire V880, Sun Ultra 80, NEC TX7/i6010 and SGI Altix 3700. The OSCAR compiler hierarchically exploits the coarse grain task parallelism among loops, subroutines and basic blocks and the near fine grain parallelism among statements inside a basic block in addition to the loop parallelism. Also, it allows us global cache optimization over different loops, or coarse grain tasks, based on data localization technique with inter-array padding to reduce memory access overhead. Current performance of OSCAR compiler is evaluated on the above SMP servers. For example, the OSCAR compiler generating OpenMP parallelized programs from ordinary sequential Fortran programs gives us 5.7 times speedup, in the average of seven programs, such as SPEC CFP95 tomcatv, swim, su2cor, hydro2d, mgrid, applu and turb3d, compared with IBM XL Fortran compiler 8.1 on IBM pSeries 690 24 processors SMP server. Also, it gives us 2.6 times speedup compare with Intel Fortran Itanium Compiler 7.1 on SGI Altix 3700 Itanium 2 16 processors server, 1.7 times speedup compared with NEC Fortran Itanium Compiler 3.4 on NEC TX7/i6010 Itanium 2 8 processors server, 2.5 times speedup compared with Sun Forte 7.0 on Sun Ultra 80 UltraSPARC II 4 processors desktop workstation, and 2.1 times speedup compare with Sun Forte compiler 7.1 on Sun Fire V880 UltraSPARC III Cu 8 processors server.