Transcript Case Study: PETSc ex19 Non-linear solver (snes)

Case Study: PETSc ex19
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Non-linear solver (snes)
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2-D driven cavity code
uses velocity-velocity formulation
finite difference discretization on a structured grid
Instrumentation:
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MPI
 MPI
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wrapper interposition library
PDT (tau_instrumentor)
 PETSc
library sources
 Application
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Selective instrumentation (tau_reduce)
Configuring TAU
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Profiling with wallclock time (on a quad PIII Linux machine)
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Tracing
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% configure –mpiinc=/usr/local/packages/mpich/include
–mpilib=/usr/local/packages/mpich/lib –pdt=/usr/pkg/pdtoolkit/
-useropt=-O2 –LINUXTIMERS
% configure –mpiinc=/usr/local/packages/mpich/include
–mpilib=/usr/local/packages/mpich/lib –pdt=/usr/pkg/pdtoolkit
–useropt=-O2 –LINUXTIMERS
Profiling with PAPI
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% configure –mpiinc=/usr/local/packages/mpich/include
–mpilib=/usr/local/packages/mpich/lib –pdt=/usr/pkg/pdtoolkit/
-useropt=-O2 –papi=/usr/local/packages/papi
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% setenv PAPI_EVENT PAPI_FP_INS
% setenv PAPI_EVENT PAPI_L1_DCM
Compiling: TAU Makefiles
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Include TAU Stub Makefile (<arch>/lib) in the user’s Makefile.
Variables:
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TAU_CXX
Specify the C++ compiler used by TAU
TAU_CC, TAU_F90
Specify the C, F90 compilers
TAU_DEFS
Defines used by TAU. Add to CFLAGS
TAU_LDFLAGS
Linker options. Add to LDFLAGS
TAU_INCLUDE
Header files include path. Add to CFLAGS
TAU_LIBS
Statically linked TAU library. Add to LIBS
TAU_SHLIBS
Dynamically linked TAU library
TAU_MPI_LIBS
TAU’s MPI wrapper library for C/C++
TAU_MPI_FLIBS
TAU’s MPI wrapper library for F90
TAU_FORTRANLIBS Must be linked in with C++ linker for F90.
TAU_DISABLETAU’s dummy F90 stub library
Note: Not including TAU_DEFS in CFLAGS disables
instrumentation in C/C++ programs (TAU_DISABLE for f90).
Profiling ex19 (wallclock time)
Profiling ex19 (wallclock time)
Tracing ex19
Callgraph Display for ex19
Using TAU with PAPI (PAPI_FP_INS)
Using TAU with PAPI (PAPI_L1_DCM)
Using TAU with PAPI (PAPI_FP_INS)
Using TAU with PAPI (PAPI_FP_INS)
Support Acknowledgement
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TAU and PDT support:
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Department of Energy (DOE)
 DOE
2000 ACTS contract
 DOE MICS contract
 DOE ASCI Level 3 (LANL, LLNL)
 U. of Utah DOE ASCI Level 1 subcontract
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DARPA
NSF National Young Investigator (NYI) award