diff --git a/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/jobgen/impl/PlanCompiler.java b/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/jobgen/impl/PlanCompiler.java
index bbe8fb3..63a6852 100644
--- a/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/jobgen/impl/PlanCompiler.java
+++ b/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/jobgen/impl/PlanCompiler.java
@@ -54,6 +54,8 @@
         operatorVisitedToParents.clear();
         builder.buildSpec(rootOps);
         spec.setConnectorPolicyAssignmentPolicy(new ConnectorPolicyAssignmentPolicy());
+        // Do not do activity cluster planning because it is slow on large clusters
+        spec.setUseConnectorPolicyForScheduling(false);
         return spec;
     }