include/split.h

   1 /*
   2  *
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   4  *
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   7  *          GROningen MAchine for Chemical Simulations
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   9  *                        VERSION 3.2.0
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  35
  36 #ifndef _split_h
  37 #define _split_h
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include <config.h>
  41 #endif
  42
  43 /*
  44  * Determine on which node a particle should reside and on which
  45  * node is also should be available. The distribution algorithm
  46  * should account for the actual ring architecture and how nodes
  47  * are numbered. The typedef t_splitd has two separate structures that
  48  * describe the distribution:
  49  *
  50  * The nodeinfo part describes which node containst which particles,
  51  * while the nodeids part describes on which node(s) a particle can be
  52  * found and what local particle number is assigned to it.
  53  *
  54  */
  55
  56 #include <stdio.h>
  57 #include "typedefs.h"
  58
  59 #ifdef __cplusplus
  60 extern "C" {
  61 #endif
  62
  63 typedef enum {SPLIT_NONE,SPLIT_SORTX,SPLIT_REDUCE,SPLIT_NR} t_splitalg;
  64
  65 typedef struct
  66 {
  67   int hid;
  68   atom_id *nodeid;
  69 } t_nodeids;
  70
  71 typedef struct
  72 {
  73   int nr;               /* Length of the long list.                         */
  74   int *lst;             /* The actual list.                                 */
  75 } t_nlist;
  76
  77 typedef struct
  78 {
  79   t_nlist home;         /* List of home particles.                          */
  80 } t_nodeinfo;
  81
  82 typedef struct
  83 {
  84   int nnodes;           /* Number of nodes this splitinfo is for.      */
  85   t_nodeinfo *nodeinfo; /* Home and available particles for each node. */
  86   int nnodeids;         /* Number of particles this splitinfo is for.       */
  87   t_nodeids *nodeids;   /* List of node id's for every particle,       */
  88                         /* entry[nodeid] gives the local atom id (NO_ATID if*/
  89                         /* not available). Entry[MAXNODES] contains home    */
  90                         /* node's id.                                  */
  91 } t_splitd;
  92
  93 extern void init_splitd(t_splitd *splitd,int nnodes,int nnodeids);
  94      /*
  95       * Initialises the splitd data structure for the specified number of
  96       * nodes (nnodes) and number of atoms (nnodeids).
  97       */
  98
  99 extern void make_splitd(t_splitalg algorithm,int nnodes,t_topology *top,
 100                         rvec *x,t_splitd *splitd,char *loadfile);
 101      /*
 102       * Initialises the splitd data structure for the specified number of
 103       * nodes (nnodes) and number of atoms (top) and fills it using
 104       * the specified algorithm (algorithm):
 105       *
 106       *    SPLIT_NONE   : Generate partial systems by dividing it into nnodes
 107       *                   consecutive, equal, parts without any intelligence.
 108       *    SPLIT_SORTX  : Like SPLIT_NONE but sort the coordinates before
 109       *                   dividing the system into nnodes consecutive, equal,
 110       *                   parts.
 111       *    SPLIT_REDUCE : Like SPLIT_NONE but minimise the bond lengths, i.e
 112       *                   invoke the reduce algorithm before dividing the
 113       *                   system into nnodes consecutive, equal, parts.
 114       *
 115       * The topology (top) and the coordinates (x) are not modified. The
 116       * calculations of bonded forces are assigned to the node with
 117       * the highest id that has one of the needed particles as home particle.
 118       */
 119
 120 extern long wr_split(FILE *fp,t_splitd *splitd);
 121      /*
 122       * Writes the split descriptor (splitd) to the file specified by fp.
 123       */
 124
 125 extern long rd_split(FILE *fp,t_splitd *splitd);
 126      /*
 127       * Reads the split descriptor (splitd) from the file specified by fp.
 128       */
 129
 130 extern void rm_splitd(t_splitd *splitd);
 131      /*
 132       * Frees all allocated space for the splitd data structure.
 133       */
 134
 135 extern void pr_splitd(FILE *fp,int indent,char *title,t_splitd *splitd);
 136      /*
 137       * This routine prints out a (human) readable representation of
 138       * the split descriptor to the file fp. Ident specifies the
 139       * number of spaces the text should be indented. Title is used
 140       * to print a header text.
 141       */
 142
 143 extern void split_topology(t_splitalg algorithm,int nnodes,t_topology *top,
 144                            rvec x[],char *loadfile);
 145      /*
 146       * Distributes the non-bonded forces defined in top over nnodes nodes
 147       * using the algoritm specified by algorithm. The distribution is made
 148       * by creating a split descriptor and then putting a bonded force on the
 149       * highest home node number of the paricles involved.
 150       */
 151
 152 #ifdef __cplusplus
 153 }
 154 #endif
 155
 156 #endif  /* _split_h */