Fix bug with DD for dims without PBC

When using DD along dimensions without PBC, many pair forces could
be missing. This would not cause silent errors, except when only
running a few steps.

Fixes #2736

Change-Id: Ia256b907e25eef811e1c8f348dc0a78aaddb5610

diff --git a/src/gromacs/domdec/domdec_internal.h b/src/gromacs/domdec/domdec_internal.h
index 83d8fc5709278c02a59df3a9dfe800f423ea10d4..f5754a7f2fd72e8293c384a0ca962821999e4814 100644 (file)
--- a/src/gromacs/domdec/domdec_internal.h
+++ b/src/gromacs/domdec/domdec_internal.h
@@ -275,10 +275,11 @@ struct gmx_ddzone_t
     real mch1;    /* The maximum top communicaton height for this zone      */
     real p1_0;    /* The bottom value of the first cell in this zone        */
     real p1_1;    /* The top value of the first cell in this zone           */
+    real dataSet; /* Bool disguised as a real, 1 when the above data has been set. 0 otherwise */
 };
 
 /*! \brief The number of reals in gmx_ddzone_t */
-constexpr int c_ddzoneNumReals = 7;
+constexpr int c_ddzoneNumReals = 8;
 
 template<typename T> class DDBufferAccess;
 

diff --git a/src/gromacs/domdec/partition.cpp b/src/gromacs/domdec/partition.cpp
index 7d9e8b6cd9b7aacdd6d863c6d75b1d815641e17f..a81ab75ef2994392e827e36bf80fcf24c6edfdf0 100644 (file)
--- a/src/gromacs/domdec/partition.cpp
+++ b/src/gromacs/domdec/partition.cpp
@@ -149,13 +149,14 @@ static void dd_move_cellx(gmx_domdec_t      *dd,
         gmx_ddzone_t &zp  = (d == 1) ? comm->zone_d1[0] : comm->zone_d2[0][0];
 
         /* Copy the base sizes of the home zone */
-        zp.min0 = cell_ns_x0[dim];
-        zp.max1 = cell_ns_x1[dim];
-        zp.min1 = cell_ns_x1[dim];
-        zp.mch0 = cell_ns_x0[dim];
-        zp.mch1 = cell_ns_x1[dim];
-        zp.p1_0 = cell_ns_x0[dim];
-        zp.p1_1 = cell_ns_x1[dim];
+        zp.min0    = cell_ns_x0[dim];
+        zp.max1    = cell_ns_x1[dim];
+        zp.min1    = cell_ns_x1[dim];
+        zp.mch0    = cell_ns_x0[dim];
+        zp.mch1    = cell_ns_x1[dim];
+        zp.p1_0    = cell_ns_x0[dim];
+        zp.p1_1    = cell_ns_x1[dim];
+        zp.dataSet = 1;
     }
 
     gmx::ArrayRef<DDCellsizesWithDlb> cellsizes = comm->cellsizesWithDlb;
@@ -180,15 +181,18 @@ static void dd_move_cellx(gmx_domdec_t      *dd,
          */
         for (int d1 = d; d1 < dd->ndim-1; d1++)
         {
+            gmx_ddzone_t &buf = buf_s[pos];
+
             /* We invert the order to be able to use the same loop for buf_e */
-            buf_s[pos].min0 = extr_s[d1][1];
-            buf_s[pos].max1 = extr_s[d1][0];
-            buf_s[pos].min1 = extr_s[d1][2];
-            buf_s[pos].mch0 = 0;
-            buf_s[pos].mch1 = 0;
+            buf.min0    = extr_s[d1][1];
+            buf.max1    = extr_s[d1][0];
+            buf.min1    = extr_s[d1][2];
+            buf.mch0    = 0;
+            buf.mch1    = 0;
             /* Store the cell corner of the dimension we communicate along */
-            buf_s[pos].p1_0 = comm->cell_x0[dim];
-            buf_s[pos].p1_1 = 0;
+            buf.p1_0    = comm->cell_x0[dim];
+            buf.p1_1    = 0;
+            buf.dataSet = 1;
             pos++;
         }
 
@@ -356,6 +360,20 @@ static void dd_move_cellx(gmx_domdec_t      *dd,
                     pos++;
                 }
             }
+            else
+            {
+                if (d == 1 || (d == 0 && dd->ndim == 3))
+                {
+                    for (int i = d; i < 2; i++)
+                    {
+                        comm->zone_d2[1 - d][i].dataSet = 0;
+                    }
+                }
+                if (d == 0)
+                {
+                    comm->zone_d1[1].dataSet = 0;
+                }
+            }
         }
     }
 
@@ -364,12 +382,15 @@ static void dd_move_cellx(gmx_domdec_t      *dd,
         int dim = dd->dim[1];
         for (int i = 0; i < 2; i++)
         {
-            if (debug)
+            if (comm->zone_d1[i].dataSet != 0)
             {
-                print_ddzone(debug, 1, i, 0, &comm->zone_d1[i]);
+                if (debug)
+                {
+                    print_ddzone(debug, 1, i, 0, &comm->zone_d1[i]);
+                }
+                cell_ns_x0[dim] = std::min(cell_ns_x0[dim], comm->zone_d1[i].min0);
+                cell_ns_x1[dim] = std::max(cell_ns_x1[dim], comm->zone_d1[i].max1);
             }
-            cell_ns_x0[dim] = std::min(cell_ns_x0[dim], comm->zone_d1[i].min0);
-            cell_ns_x1[dim] = std::max(cell_ns_x1[dim], comm->zone_d1[i].max1);
         }
     }
     if (dd->ndim >= 3)
@@ -379,12 +400,15 @@ static void dd_move_cellx(gmx_domdec_t      *dd,
         {
             for (int j = 0; j < 2; j++)
             {
-                if (debug)
+                if (comm->zone_d2[i][j].dataSet != 0)
                 {
-                    print_ddzone(debug, 2, i, j, &comm->zone_d2[i][j]);
+                    if (debug)
+                    {
+                        print_ddzone(debug, 2, i, j, &comm->zone_d2[i][j]);
+                    }
+                    cell_ns_x0[dim] = std::min(cell_ns_x0[dim], comm->zone_d2[i][j].min0);
+                    cell_ns_x1[dim] = std::max(cell_ns_x1[dim], comm->zone_d2[i][j].max1);
                 }
-                cell_ns_x0[dim] = std::min(cell_ns_x0[dim], comm->zone_d2[i][j].min0);
-                cell_ns_x1[dim] = std::max(cell_ns_x1[dim], comm->zone_d2[i][j].max1);
             }
         }
     }