include/split.h

   1 /*
   2  * $Id$
   3  *
   4  *       This source code is part of
   5  *
   6  *        G   R   O   M   A   C   S
   7  *
   8  * GROningen MAchine for Chemical Simulations
   9  *
  10  *               VERSION 2.0
  11  *
  12  * Copyright (c) 1991-1999
  13  * BIOSON Research Institute, Dept. of Biophysical Chemistry
  14  * University of Groningen, The Netherlands
  15  *
  16  * Please refer to:
  17  * GROMACS: A message-passing parallel molecular dynamics implementation
  18  * H.J.C. Berendsen, D. van der Spoel and R. van Drunen
  19  * Comp. Phys. Comm. 91, 43-56 (1995)
  20  *
  21  * Also check out our WWW page:
  22  * http://md.chem.rug.nl/~gmx
  23  * or e-mail to:
  24  * gromacs@chem.rug.nl
  25  *
  26  * And Hey:
  27  * Green Red Orange Magenta Azure Cyan Skyblue
  28  */
  29
  30 #ifndef _split_h
  31 #define _split_h
  32
  33 static char *SRCID_split_h = "$Id$";
  34
  35 #ifdef HAVE_IDENT
  36 #ident  "@(#) split.h 1.20 12/16/92"
  37 #endif /* HAVE_IDENT */
  38
  39 /*
  40  * Determine on which processor a particle should reside and on which
  41  * processor is also should be available. The distribution algorithm
  42  * should account for the actual ring architecture and how processors
  43  * are numbered. The typedef t_splitd has two separate structures that
  44  * describe the distribution:
  45  *
  46  * The procinfo part describes which processor containst which particles,
  47  * while the pids part describes on which processor(s) a particle can be
  48  * found and what local particle number is assigned to it.
  49  *
  50  */
  51
  52 #include <stdio.h>
  53 #include "typedefs.h"
  54
  55 typedef enum {SPLIT_NONE,SPLIT_SORTX,SPLIT_REDUCE,SPLIT_NR} t_splitalg;
  56
  57 typedef struct
  58 {
  59   int hid;
  60   atom_id *pid;
  61 } t_pids;
  62
  63 typedef struct
  64 {
  65   int nr;               /* Length of the long list.                         */
  66   int *lst;             /* The actual list.                                 */
  67 } t_nlist;
  68
  69 typedef struct
  70 {
  71   t_nlist home;         /* List of home particles.                          */
  72 } t_procinfo;
  73
  74 typedef struct
  75 {
  76   int nprocs;           /* Number of processors this splitinfo is for.      */
  77   t_procinfo *procinfo; /* Home and available particles for each processor. */
  78   int npids;            /* Number of particles this splitinfo is for.       */
  79   t_pids *pids;         /* List of processor id's for every particle,       */
  80                         /* entry[pid] gives the local atom id (NO_ATID if   */
  81                         /* not available). Entry[MAXPROC] contains home     */
  82                         /* processor's id.                                  */
  83 } t_splitd;
  84
  85 extern void init_splitd(t_splitd *splitd,int nprocs,int npids);
  86      /*
  87       * Initialises the splitd data structure for the specified number of
  88       * processors (nprocs) and number of atoms (npids).
  89       */
  90
  91 extern void make_splitd(t_splitalg algorithm,int nprocs,t_topology *top,
  92                         rvec *x,t_splitd *splitd,char *loadfile);
  93      /*
  94       * Initialises the splitd data structure for the specified number of
  95       * processors (nprocs) and number of atoms (top) and fills it using
  96       * the specified algorithm (algorithm):
  97       *
  98       *    SPLIT_NONE   : Generate partial systems by dividing it into nprocs
  99       *                   consecutive, equal, parts without any intelligence.
 100       *    SPLIT_SORTX  : Like SPLIT_NONE but sort the coordinates before
 101       *                   dividing the system into nprocs consecutive, equal,
 102       *                   parts.
 103       *    SPLIT_REDUCE : Like SPLIT_NONE but minimise the bond lengths, i.e
 104       *                   invoke the reduce algorithm before dividing the
 105       *                   system into nprocs consecutive, equal, parts.
 106       *
 107       * The topology (top) and the coordinates (x) are not modified. The
 108       * calculations of bonded forces are assigned to the processor with
 109       * the highest id that has one of the needed particles as home particle.
 110       */
 111
 112 extern long wr_split(FILE *fp,t_splitd *splitd);
 113      /*
 114       * Writes the split descriptor (splitd) to the file specified by fp.
 115       */
 116
 117 extern long rd_split(FILE *fp,t_splitd *splitd);
 118      /*
 119       * Reads the split descriptor (splitd) from the file specified by fp.
 120       */
 121
 122 extern void rm_splitd(t_splitd *splitd);
 123      /*
 124       * Frees all allocated space for the splitd data structure.
 125       */
 126
 127 extern void pr_splitd(FILE *fp,int indent,char *title,t_splitd *splitd);
 128      /*
 129       * This routine prints out a (human) readable representation of
 130       * the split descriptor to the file fp. Ident specifies the
 131       * number of spaces the text should be indented. Title is used
 132       * to print a header text.
 133       */
 134
 135 extern void split_topology(t_splitalg algorithm,int nprocs,t_topology *top,
 136                            rvec x[],char *loadfile);
 137      /*
 138       * Distributes the non-bonded forces defined in top over nprocs processors
 139       * using the algoritm specified by algorithm. The distribution is made
 140       * by creating a split descriptor and then putting a bonded force on the
 141       * highest home processor number of the paricles involved.
 142       */
 143
 144
 145 #endif  /* _split_h */