Bad Performance on Power4/AIX

[jschmidt]

Hi,

I've just compiled CP2K on a system with Power4-processors
("Regatta"), running under AIX, and there is a problem with the
parallel version. The sdbg and sopt is fine, but as soon as I switch
to pdbg or popt (using the arch-files from the cvs) the timings are
really bad. A system with one water molecule needs about 100 secs for
initialization and again about 100 secs per MD step. Using the sopt-
version this is only about 1 sec. Here is the arch-file that I used:

PERL     = perl
CC       = cc
CPP      = /usr/ccs/lib/cpp
FC       = mpxlf95_r -qsuffix=f=f90
LD       = mpxlf95_r
AR       = ar -r
DFLAGS   = -D__AIX -D__ESSL -D__FFTSG -D__FFTESSL\
           -D__parallel -D__BLACS -D__SCALAPACK
CPPFLAGS = -C $(DFLAGS) -P
FCFLAGS  = -C -g -q32 -qarch=pwr4 -qflttrap=overflow:zerodivide:enable
\
           -qfullpath -qinitauto=FF -qnointlog -qnosave -qsigtrap -
qtune=pwr4
LDFLAGS  = $(FCFLAGS) -bnoquiet
LIBS     = -L /afs/ipp/@sys/lib -lscalapack\
           /afs/ipp/@sys/lib/blacsF77init_MPI-POWER4-0.a\
           /afs/ipp/@sys/lib/blacs_MPI-POWER4-0.a -lessl\
          -L/afs/rzg/@sys/lib -llapack-essl -lessl -lpessl -lmass -
lhmd

OBJECTS_ARCHITECTURE = machine_aix.o

Is anyone using the latest cvs-version on a such a system?

Thanks for your help!
Jochen