diff --git a/arangod/Aql/UnsortedGatherExecutor.cpp b/arangod/Aql/UnsortedGatherExecutor.cpp
index 9fff8e48b8..5f9d61ff9b 100644
--- a/arangod/Aql/UnsortedGatherExecutor.cpp
+++ b/arangod/Aql/UnsortedGatherExecutor.cpp
@@ -73,12 +73,9 @@ std::pair<ExecutionState, NoStats> UnsortedGatherExecutor::produceRows(OutputAql
   ExecutionState state;
   InputAqlItemRow inputRow = InputAqlItemRow{CreateInvalidInputRowHint{}};
   
-  bool more = false;
-  bool waiting = false;
-  
-  size_t i = _currentDependency;
-  for (size_t x = 0; x < _numberDependencies; ++x) {
-    i = (_currentDependency + x) % _numberDependencies;
+  size_t x;
+  for (x = 0; x < _numberDependencies; ++x) {
+    size_t i = (_currentDependency + x) % _numberDependencies;
   
     if (_upstream[i] == ExecutionState::DONE) {
       continue;
@@ -98,23 +95,25 @@ std::pair<ExecutionState, NoStats> UnsortedGatherExecutor::produceRows(OutputAql
     }
     
     _upstream[i] = state;
-    if (state == ExecutionState::HASMORE) {
-      more = true;
-    } else if (state == ExecutionState::WAITING) {
-      waiting = true;
-    }
     if (output.isFull()) {
       break;
     }
   }
-  _currentDependency = i;
+  _currentDependency = x;
   
   NoStats stats;
-  if (more) {
-    return {ExecutionState::HASMORE, stats};
-  } else if (waiting) {
+  size_t numWaiting = 0;
+  for (x = 0; x < _numberDependencies; ++x) {
+    if (_upstream[x] == ExecutionState::HASMORE) {
+      return {ExecutionState::HASMORE, stats};
+    } else if (_upstream[x] == ExecutionState::WAITING) {
+      numWaiting++;
+    }
+  }
+  if (numWaiting > 0) {
     return {ExecutionState::WAITING, stats};
   }
+  
   TRI_ASSERT(std::all_of(_upstream.begin(), _upstream.end(), [](auto const& s) { return s == ExecutionState::DONE; } ));
   return {ExecutionState::DONE, stats};
 }
diff --git a/arangod/Aql/UnsortedGatherExecutor.h b/arangod/Aql/UnsortedGatherExecutor.h
index 70f596f5e3..4a79e9a9f1 100644
--- a/arangod/Aql/UnsortedGatherExecutor.h
+++ b/arangod/Aql/UnsortedGatherExecutor.h
@@ -27,6 +27,7 @@
 #include "Aql/ExecutionState.h"
 #include "Aql/ExecutorInfos.h"
 #include "Aql/InputAqlItemRow.h"
+#include "Containers/SmallVector.h"
 
 namespace arangodb {
 
@@ -76,9 +77,6 @@ class UnsortedGatherExecutor {
    */
   std::pair<ExecutionState, Stats> produceRows(OutputAqlItemRow& output);
 
-//  std::pair<ExecutionState, size_t> expectedNumberOfRows(size_t atMost) const;
-//  std::tuple<ExecutionState, Stats, SharedAqlItemBlockPtr> fetchBlockForPassthrough(size_t atMost);
-
   std::tuple<ExecutionState, Stats, size_t> skipRows(size_t atMost);
   
  private:
@@ -88,7 +86,8 @@ class UnsortedGatherExecutor {
  private:
   Fetcher& _fetcher;
   
-  std::vector<ExecutionState> _upstream;
+  ::arangodb::containers::SmallVector<ExecutionState>::allocator_type::arena_type _arena;
+  ::arangodb::containers::SmallVector<ExecutionState> _upstream{_arena};
 
   // Total Number of dependencies
   size_t _numberDependencies;