Require fewer measurements to scale containers

2 files changed, 9 insertions, 5 deletions

diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/Autoscaler.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/Autoscaler.java
index 1ba03a7c9bc..ba63376d61e 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/Autoscaler.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/Autoscaler.java
@@ -20,8 +20,6 @@ import java.util.stream.Collectors;
  */
 public class Autoscaler {
 
-    private static final int minimumMeasurementsPerNode = 60; // 1 hour
-
     /** What cost difference factor is worth a reallocation? */
     private static final double costDifferenceWorthReallocation = 0.1;
     /** What difference factor for a resource is worth a reallocation? */
@@ -106,18 +104,24 @@ public class Autoscaler {
 
         // Require a total number of measurements scaling with the number of nodes,
         // but don't require that we have at least that many from every node
-        if (window.measurementCount()/clusterNodes.size() < minimumMeasurementsPerNode) return Optional.empty();
+        if (window.measurementCount()/clusterNodes.size() < minimumMeasurementsPerNode(clusterType)) return Optional.empty();
         if (window.hostnames() != clusterNodes.size()) return Optional.empty();
 
         return Optional.of(window.average());
     }
 
-    /** The duration of the window we need to consider to make a scaling decision */
+    /** The duration of the window we need to consider to make a scaling decision. See also minimumMeasurementsPerNode */
     static Duration scalingWindow(ClusterSpec.Type clusterType) {
         if (clusterType.isContent()) return Duration.ofHours(12);
         return Duration.ofHours(1);
     }
 
+    /** Measurements are currently taken once a minute. See also scalingWindow */
+    static int minimumMeasurementsPerNode(ClusterSpec.Type clusterType) {
+        if (clusterType.isContent()) return 60;
+        return 20;
+    }
+
     public static boolean unstable(List<Node> nodes) {
         return nodes.stream().anyMatch(node -> node.status().wantToRetire() ||
                                                node.allocation().get().membership().retired() ||
diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/NodeMetricsDb.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/NodeMetricsDb.java
index 48bcd435806..316708732a7 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/NodeMetricsDb.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/NodeMetricsDb.java
@@ -63,7 +63,7 @@ public class NodeMetricsDb {
     public void gc(Clock clock) {
         synchronized (lock) {
             // Each measurement is Object + long + float = 16 + 8 + 4 = 28 bytes
-            // 24 hours with 1k nodes and 3 resources and 1 measurement/sec is about 10Gb
+            // 12 hours with 1k nodes and 3 resources and 1 measurement/sec is about 5Gb
 
             for (Iterator<NodeMeasurements> i = db.values().iterator(); i.hasNext(); ) {
                 var measurements = i.next();