C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/eesupp/inc/GLOBAL_MAX.h,v 1.3 2001/09/21 03:54:35 cnh Exp $
C $Name:  $
CBOP
C     !ROUTINE: GLOBAL_MAX.h
C     !INTERFACE:
C     include "GLOBAL_MAX.h"
C     !DESCRIPTION:
C     *==========================================================*
C     | GLOBAL_MAX.h                                              
C     | o Globals used by Fortran global max routine.             
C     *==========================================================*
C     | The global max shared memory scheme uses global heap data 
C     | structures (.i.e COMMON blocks ). Each thread writes to   
C     | an its own element of the shared memory array and then    
C     | one thread reads all the entries and maxs them. The max   
C     | result is then read by all threads.                       
C     | Remember - you are working with regions of memory that    
C     | are being updated concurrently by different threads.      
C     | What happens, when it happens and who gets to see what    
C     | happens at what stage depends on the computer systems     
C     | memory model. Every computer has a different memory model 
C     | and they are never simple. In all current platforms it is 
C     | possible for one thread to see events happening in a      
C     | different order from the order they are written in the    
C     | code.                                                     
C     | Unless you understand this it is not a good idea to       
C     | make modifications te way these header files are setup or 
C     | the way the global sum routines work.                     
C     *==========================================================*
CEOP
      COMMON / GMAX_COMMON_R8 / phiGMRL
      Real*8  phiGMRL(lShare8, MAX_NO_THREADS )

      COMMON / GMAX_COMMON_R4 / phiGMRS
      Real*4  phiGMRS(lShare4, MAX_NO_THREADS )

      COMMON / GMAX_COMMON_I  / phiGMI
      INTEGER phiGMI (lShare4, MAX_NO_THREADS )