RtiWeb
diff --git a/‎CHANGELOG
Lines changed: 0 additions & 3 deletions b/‎CHANGELOG
Lines changed: 0 additions & 3 deletions
diff --git a/‎arangod/Aql/OptimizerRules.cpp
Lines changed: 5 additions & 37 deletions b/‎arangod/Aql/OptimizerRules.cpp
Lines changed: 5 additions & 37 deletions
@@ -176,9 +176,6 @@ devel
   honored and the soft limit will be set to either hard limit or system limit
   whichever is lower.
 
-* Allow an INSERT operation for a multi-shard collection to execute in 
-  parallel on different DB servers.
-
 * Fix BTS-409: return error 1948 when a negative edge was detected during or was
   used as default weight in a SHORTEST_PATH or a K_SHOTRTEST_PAHS traversal.
 
 
@@ -7426,14 +7426,10 @@ struct ParallelizableFinder final
     : public WalkerWorker<ExecutionNode, WalkerUniqueness::NonUnique> {
   bool const _parallelizeWrites;
   bool _isParallelizable;
-  bool _seenDistribute;
-  uint32_t _numRemotes;
 
   explicit ParallelizableFinder(bool parallelizeWrites)
       : _parallelizeWrites(parallelizeWrites),
-        _isParallelizable(true),
-        _seenDistribute(false),
-        _numRemotes(0) {}
+        _isParallelizable(true) {}
 
   ~ParallelizableFinder() = default;
 
@@ -7443,38 +7439,11 @@ struct ParallelizableFinder final
 
   bool before(ExecutionNode* node) override final {
     if (node->getType() == ExecutionNode::SCATTER ||
-        node->getType() == ExecutionNode::GATHER) {
+        node->getType() == ExecutionNode::GATHER ||
+        node->getType() == ExecutionNode::DISTRIBUTE) {
       _isParallelizable = false;
       return true;  // true to abort the whole walking process
     }
-    if (node->getType() == ExecutionNode::DISTRIBUTE) {
-      if (_seenDistribute) {
-        // if we find 2 DISTRIBUTE nodes in the plan, or a DISTRIBUTE
-        // at an unexpected place, we give up
-        _isParallelizable = false;
-        return true;
-      }
-      // note that we have seen a DISTRIBUTE node.
-      // note that a single DISTRIBUTE node should be safe if it
-      // itself does not reach out to other snippets.
-      // The reason it should be safe is that the DISTRIBUTE will
-      // be executed under the snippet's mutex, so any real parallelism
-      // on the same DISTRIBUTE node is prevented. if multiple
-      // DB ervers are queuing for the same DISTRIBUTE node, this may
-      // lead to some contention, but should work eventually.
-      _seenDistribute = true;
-    }
-    if (node->getType() == ExecutionNode::REMOTE) {
-      // plan walking starts at a GATHER node, so we expect to see
-      // at least one REMOTE node.
-      // if we find another one, it is ok if that REMOTE node refers
-      // to a DISTRIBUTE node (checked above). if it refers to another
-      // GATHER node somewhere, we also abort above.
-      if (++_numRemotes > 2 || _seenDistribute) {
-        _isParallelizable = false;
-        return true;
-      }
-    }
 
     if (node->getType() == ExecutionNode::TRAVERSAL ||
         node->getType() == ExecutionNode::SHORTEST_PATH ||
@@ -7493,7 +7462,6 @@ struct ParallelizableFinder final
         (!_parallelizeWrites ||
          (node->getType() != ExecutionNode::REMOVE &&
           node->getType() != ExecutionNode::REPLACE &&
-          node->getType() != ExecutionNode::INSERT &&
           node->getType() != ExecutionNode::UPDATE))) {
       _isParallelizable = false;
       return true;  // true to abort the whole walking process
@@ -7838,10 +7806,10 @@ void arangodb::aql::parallelizeGatherRule(Optimizer* opt,
   ::arangodb::containers::SmallVector<ExecutionNode*> nodes{a};
   plan->findNodesOfType(nodes, EN::GATHER, true);
 
-  if (nodes.size() == 1 && !plan->contains(EN::SCATTER)) {
-    GatherNode* gn = ExecutionNode::castTo<GatherNode*>(nodes[0]);
+  if (nodes.size() == 1 && !plan->contains(EN::DISTRIBUTE) && !plan->contains(EN::SCATTER)) {
     TRI_vocbase_t& vocbase = plan->getAst()->query().vocbase();
     bool parallelizeWrites = vocbase.server().getFeature<OptimizerRulesFeature>().parallelizeGatherWrites();
+    GatherNode* gn = ExecutionNode::castTo<GatherNode*>(nodes[0]);
 
     if (!gn->isInSubquery() && isParallelizable(gn, parallelizeWrites)) {
       // find all graph nodes and make sure that they all are using satellite