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Trouble shooting and clues on various computers

MM5 Model on PC

Complie Options for PC Running Linux and pgf77/pgf90 Compiler

If you are trying to compile and run MM5 model on a PC, the following describes the changes you need to make to configure.user file and mm5.deck. There is no change required in the Fortran source code. To see the PC timing result, click here.

Note that to run the MM5 model on a PC, it requires Linux and Portland Group Inc. Fortran compiler version 1.6 and above. The input data format is the standard workstation 32-bit IEEE data. You may download Linux from their web page.

The compiler options are in the configure.user.linux:

#-----------------------------------------------------------------------------
# 3i1. PC (LINUX/Portland Group Inc.)
# pgf77 version 1.6 and above
#-----------------------------------------------------------------------------
FC = pgf77
FCFLAGS = -I$(LIBINCLUDE) -O2 -Mcray=pointer -tp p6 -pc 32 -Mnoframe -byteswapio
#FCFLAGS = -I$(LIBINCLUDE) -O2 -Mcray=pointer -tp p6 -pc 32 -Mnoframe -byteswapio -mp
#-Mnosgimp
CPP = /lib/cpp
CFLAGS = -O
CPPFLAGS = -I$(LIBINCLUDE)
LDOPTIONS = -O2 -Mcray=pointer -tp p6 -pc 32 -Mnoframe -byteswapio
#LDOPTIONS = -O2 -Mcray=pointer -tp p6 -pc 32 -Mnoframe -byteswapio -mp
LOCAL_LIBRARIES =
MAKE = make -i
#-----------------------------------------------------------------------------

It is also recommended to remove the following section in configure.user file, since pgf77 supports cpp:

.F.i:
        $(RM) $@
        $(CPP) $(CPPFLAGS) $*.F > $@
        mv $*.i $(DEVTOP)/pick/$*.f
        cp $*.F $(DEVTOP)/pick

(The above is provided by George Lai of NASA/GODDARD)

Update (4/19/01)

If you have RedHat 6.2 and default kernal (version 2.2.14-5.0), you may encounter strange problem with MM5 runs (such as CFL error appearing randomly in a run). In this case you should definitely upgrade the kernal as there is a known problem with this default one which, according to an expert, 'contains a bug that can result in data corruption under heavy load'. The recommended 2.2.14 kernel is 2.2.14-6.0.2 or later ones.

Update (9/6/00)

Add -Kieee compile option if you choose to use Gayno-Seaman PBL scheme. Without this option, MM5 fails immediately with 'NaN' and then CFL problem.

Update (7/12/99)

With newer version of PGF compiler, you may compile for multi-processor PC runs with -Mnosgimp option added to FCFLAGS and LDOPTIONS. This allows user to use OpenMP parallel directives and deactivate SGI parallel directives.

If you are getting strange error when running the model (such as 'Segmentation fault'), it may be due to lack of stack size. Use the following to increase stack size:

       setenv MPSTKZ 8M

Or type

       limit stacksize unlimited

Also look for help in PGI User's Guide. (Thanks to Michael Morgan of University of Wiscousin.)

Changes to mm5.deck

All Fortran units need to be change from fort.xx to FTNxxx. For example,

    fort.8  --> FTN008
    fort.11 --> FTN011

You may not need to do so with newer compiler from PGF.

Update (4/21/98)

• If you have difficulty compiling, you may try to remove another rule near the bottom of the configure.user file:

  .F.f:
  $(RM) $@
  $(CPP) $(CPPFLAGS) $*.F > $@

• If you have pgf77 1.7 and above, you won't need to change the fortran units in a mm5.deck: fort.10 etc. work fine for those compilers.