Consider switching cost when choosing host flavor

2 files changed, 19 insertions, 21 deletions

diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocatableClusterResources.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocatableClusterResources.java
index 0f100593e38..a4e1a62f5b9 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocatableClusterResources.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocatableClusterResources.java
@@ -10,6 +10,7 @@ import com.yahoo.vespa.hosted.provision.Node;
 import com.yahoo.vespa.hosted.provision.NodeList;
 import com.yahoo.vespa.hosted.provision.NodeRepository;
 
+import java.time.Duration;
 import java.util.List;
 import java.util.Optional;
 
@@ -129,11 +130,18 @@ public class AllocatableClusterResources {
         return (vcpuFulfilment + memoryGbFulfilment + diskGbFulfilment) / 3;
     }
 
-    public boolean preferableTo(AllocatableClusterResources other) {
-        if (this.fulfilment < 1 || other.fulfilment < 1) // always fulfil as much as possible
-            return this.fulfilment > other.fulfilment;
+    public boolean preferableTo(AllocatableClusterResources other,
+                                AllocatableClusterResources current, ClusterModel clusterModel) {
+        if (other.fulfilment() < 1 || this.fulfilment() < 1) // always fulfil as much as possible
+            return this.fulfilment() > other.fulfilment();
 
-        return this.cost() < other.cost(); // otherwise, prefer lower cost
+        return this.cost() * toHours(clusterModel.allocationDuration()) + this.costChangingFrom(current, clusterModel)
+               <
+               other.cost() * toHours(clusterModel.allocationDuration()) + other.costChangingFrom(current, clusterModel);
+    }
+
+    private double toHours(Duration duration) {
+        return duration.toMillis() / 3600000.0;
     }
 
     /** The estimated cost of changing from the given current resources to this. */
@@ -165,6 +173,8 @@ public class AllocatableClusterResources {
                                                              ClusterSpec clusterSpec,
                                                              Limits applicationLimits,
                                                              List<NodeResources> availableRealHostResources,
+                                                             AllocatableClusterResources current,
+                                                             ClusterModel clusterModel,
                                                              NodeRepository nodeRepository) {
         var systemLimits = nodeRepository.nodeResourceLimits();
         boolean exclusive = nodeRepository.exclusiveAllocation(clusterSpec);
@@ -228,12 +238,12 @@ public class AllocatableClusterResources {
                                                                 clusterSpec);
 
                 if ( ! systemLimits.isWithinAdvertisedDiskLimits(advertisedResources, clusterSpec)) { // TODO: Remove when disk limit is enforced
-                    if (bestDisregardingDiskLimit.isEmpty() || candidate.preferableTo(bestDisregardingDiskLimit.get())) {
+                    if (bestDisregardingDiskLimit.isEmpty() || candidate.preferableTo(bestDisregardingDiskLimit.get(), current, clusterModel)) {
                         bestDisregardingDiskLimit = Optional.of(candidate);
                     }
                     continue;
                 }
-                if (best.isEmpty() || candidate.preferableTo(best.get())) {
+                if (best.isEmpty() || candidate.preferableTo(best.get(), current, clusterModel)) {
                     best = Optional.of(candidate);
                 }
             }
diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocationOptimizer.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocationOptimizer.java
index 2511f17ee1a..deff92628e7 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocationOptimizer.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/AllocationOptimizer.java
@@ -65,29 +65,17 @@ public class AllocationOptimizer {
                                                                             current.clusterSpec(),
                                                                             limits,
                                                                             availableRealHostResources,
+                                                                            current,
+                                                                            clusterModel,
                                                                             nodeRepository);
                 if (allocatableResources.isEmpty()) continue;
-                if (bestAllocation.isEmpty() || preferableTo(bestAllocation.get(), allocatableResources.get(), current, clusterModel))
+                if (bestAllocation.isEmpty() || allocatableResources.get().preferableTo(bestAllocation.get(), current, clusterModel))
                     bestAllocation = allocatableResources;
             }
         }
         return bestAllocation;
     }
 
-    private boolean preferableTo(AllocatableClusterResources best, AllocatableClusterResources considered,
-                                 AllocatableClusterResources current, ClusterModel clusterModel) {
-        if (best.fulfilment() < 1 || considered.fulfilment() < 1) // always fulfil as much as possible
-            return considered.fulfilment() > best.fulfilment();
-
-        return considered.cost() * toHours(clusterModel.allocationDuration()) + considered.costChangingFrom(current, clusterModel)
-               <
-               best.cost() * toHours(clusterModel.allocationDuration()) + best.costChangingFrom(current, clusterModel);
-    }
-
-    private double toHours(Duration duration) {
-        return duration.toMillis() / 3600000.0;
-    }
-
     /** Returns the max resources of a host one node may allocate. */
     private NodeResources maxResourcesOf(NodeResources hostResources, ClusterModel clusterModel) {
         if (nodeRepository.exclusiveAllocation(clusterModel.clusterSpec())) return hostResources;