#2074: Disallow operating on non-consecutive phases

DARMA-tasking · Sep 20, 2024 · 0623eb1 · 0623eb1
1 parent a08b77e
commit 0623eb1
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Showing 3 changed files with 26 additions and 45 deletions.
diff --git a/src/vt/vrt/collection/balance/lb_data_restart_reader.cc b/src/vt/vrt/collection/balance/lb_data_restart_reader.cc
@@ -162,34 +162,32 @@ void LBDataRestartReader::determinePhasesToMigrate() {
 
   auto const this_node = theContext()->getNode();
   runInEpochCollective("LBDataRestartReader::updateLocations", [&]{
-    PhaseType curr = 0, next;
-    for (;curr < num_phases_ - 1;) {
-      next = findNextPhase(curr);
-
-      local_changed_distro[curr] = *history_[curr] != *history_[next];
-      if (local_changed_distro[curr]) {
-        std::set<ElementIDStruct> departing, arriving;
-
-        std::set_difference(
-          history_[next]->begin(), history_[next]->end(),
-          history_[curr]->begin(), history_[curr]->end(),
-          std::inserter(arriving, arriving.begin())
-        );
-
-        std::set_difference(
-          history_[curr]->begin(), history_[curr]->end(),
-          history_[next]->begin(), history_[next]->end(),
-          std::inserter(departing, departing.begin())
-        );
-
-        for (auto&& d : departing) {
-          proxy_[d.getHomeNode()].send<DepartMsg, &LBDataRestartReader::departing>(this_node, next, d);
-        }
-        for (auto&& a : arriving) {
-          proxy_[a.getHomeNode()].send<ArriveMsg, &LBDataRestartReader::arriving>(this_node, next, a);
+    for (PhaseType curr = 0; curr < num_phases_ - 1; ++curr) {
+      if(history_.count(curr) && history_.count(curr + 1)) {
+        local_changed_distro[curr] = *history_[curr] != *history_[curr + 1];
+        if (local_changed_distro[curr]) {
+          std::set<ElementIDStruct> departing, arriving;
+
+          std::set_difference(
+            history_[curr + 1]->begin(), history_[curr + 1]->end(),
+            history_[curr]->begin(),     history_[curr]->end(),
+            std::inserter(arriving, arriving.begin())
+          );
+
+          std::set_difference(
+            history_[curr]->begin(),     history_[curr]->end(),
+            history_[curr + 1]->begin(), history_[curr + 1]->end(),
+            std::inserter(departing, departing.begin())
+          );
+
+          for (auto&& d : departing) {
+            proxy_[d.getHomeNode()].send<DepartMsg, &LBDataRestartReader::departing>(this_node, curr + 1, d);
+          }
+          for (auto&& a : arriving) {
+            proxy_[a.getHomeNode()].send<ArriveMsg, &LBDataRestartReader::arriving>(this_node, curr + 1, a);
+          }
         }
       }
-      curr = next;
     }
   });
 

diff --git a/src/vt/vrt/collection/balance/lb_data_restart_reader.h b/src/vt/vrt/collection/balance/lb_data_restart_reader.h
@@ -128,7 +128,7 @@ struct LBDataRestartReader : runtime::component::Component<LBDataRestartReader>
    *
    * \param[in] phase the phase
    *
-   * \return pointer to elements assigned to this node, guaranted to be not null
+   * \return pointer to elements assigned to this node, guaranteed to be not null
    */
   std::shared_ptr<const std::set<ElementIDStruct>> getDistro(PhaseType phase) const {
     auto iter = history_.find(phase);
@@ -173,19 +173,6 @@ struct LBDataRestartReader : runtime::component::Component<LBDataRestartReader>
   }
 
 private:
-  /**
-   * \brief Find the next specified phase or an identical one
-   *
-   * \param phase the current phase
-   *
-   * \return the next phase
-   */
-  PhaseType findNextPhase(PhaseType phase) const {
-    auto iter = history_.upper_bound(phase);
-    vtAssert(iter != history_.end(), "Must have a valid phase");
-    return iter->first;
-  }
-
   /**
    * \brief Reduce distribution changes globally to find where migrations need
    * to occur

diff --git a/tests/unit/lb/test_offlinelb.cc b/tests/unit/lb/test_offlinelb.cc
@@ -77,13 +77,9 @@ struct SimCol : vt::Collection<SimCol, vt::Index1D> {
 
   void sparseHandler(Msg* m){
     auto const this_node = theContext()->getNode();
-    auto const num_nodes = theContext()->getNumNodes();
-    auto const next_node = (this_node + 1) % num_nodes;
     vt_debug_print(terse, lb, "sparseHandler: idx={}: elm={}\n", getIndex(), getElmID());
-    if (m->iter == 0 or m->iter == 1 or m->iter == 2 or m->iter == 3 or m->iter == 4) {
+    if (m->iter == 0 or m->iter == 1 or m->iter == 2 or m->iter == 3 or m->iter == 4 or m->iter == 5 or m->iter == 6) {
       EXPECT_EQ(getIndex().x() / 2, this_node);
-    } else if (m->iter == 5 or m->iter == 6) {
-      EXPECT_EQ(getIndex().x() / 2, next_node);
     }
   }
 };