Merge release-2021 into master

[alexxy/gromacs.git] / src / gromacs / mdlib / vsite.cpp

diff --git a/src/gromacs/mdlib/vsite.cpp b/src/gromacs/mdlib/vsite.cpp
index d030f9d4aba335b2e3f1b592663e9d27e320473e..c3f9edb3b27d65b522f598d0cfdac1f8fa4de1f7 100644 (file)
--- a/src/gromacs/mdlib/vsite.cpp
+++ b/src/gromacs/mdlib/vsite.cpp
@@ -2760,7 +2760,16 @@ static void assignVsitesToThread(VsiteThread*                    tData,
                                    "a constructing atom that does not belong to our task, such "
                                    "vsites should be assigned to the single 'master' task");
 
-                        task = nthread + thread;
+                        if (tData->useInterdependentTask)
+                        {
+                            // Assign to the interdependent task
+                            task = nthread + thread;
+                        }
+                        else
+                        {
+                            // Assign to the separate, non-parallel task
+                            task = 2 * nthread;
+                        }
                     }
                 }
             }
@@ -3000,12 +3009,13 @@ void ThreadingInfo::setVirtualSites(ArrayRef<const InteractionList> ilists,
             }
 
             /* To avoid large f_buf allocations of #threads*vsite_atom_range
-             * we don't use task2 with more than 200000 atoms. This doesn't
-             * affect performance, since with such a large range relatively few
-             * vsites will end up in the separate task.
-             * Note that useTask2 should be the same for all threads.
+             * we don't use the interdependent tasks with more than 200000 atoms.
+             * This doesn't affect performance, since with such a large range
+             * relatively few vsites will end up in the separate task.
+             * Note that useInterdependentTask should be the same for all threads.
              */
-            tData.useInterdependentTask = (vsite_atom_range <= 200000);
+            const int c_maxNumLocalAtomsForInterdependentTask = 200000;
+            tData.useInterdependentTask = (vsite_atom_range <= c_maxNumLocalAtomsForInterdependentTask);
             if (tData.useInterdependentTask)
             {
                 size_t              natoms_use_in_vsites = vsite_atom_range;