Merge pull request #16577 from vespa-engine/bratseth/traffic-fraction

Bratseth/traffic fraction

2 files changed, 69 insertions, 0 deletions

diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/ControllerMaintenance.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/ControllerMaintenance.java
index bc0295abca3..f7ab4d30088 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/ControllerMaintenance.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/ControllerMaintenance.java
@@ -64,6 +64,7 @@ public class ControllerMaintenance extends AbstractComponent {
         maintainers.add(new HostSwitchUpdater(controller, intervals.hostSwitchUpdater));
         maintainers.add(new ReindexingTriggerer(controller, intervals.reindexingTriggerer));
         maintainers.add(new EndpointCertificateMaintainer(controller, intervals.endpointCertificateMaintainer));
+        maintainers.add(new TrafficShareUpdater(controller, intervals.trafficFractionUpdater));
     }
 
     public Upgrader upgrader() { return upgrader; }
@@ -113,6 +114,7 @@ public class ControllerMaintenance extends AbstractComponent {
         private final Duration hostSwitchUpdater;
         private final Duration reindexingTriggerer;
         private final Duration endpointCertificateMaintainer;
+        private final Duration trafficFractionUpdater;
 
         public Intervals(SystemName system) {
             this.system = Objects.requireNonNull(system);
@@ -139,6 +141,7 @@ public class ControllerMaintenance extends AbstractComponent {
             this.hostSwitchUpdater = duration(12, HOURS);
             this.reindexingTriggerer = duration(1, HOURS);
             this.endpointCertificateMaintainer = duration(12, HOURS);
+            this.trafficFractionUpdater = duration(5, MINUTES);
         }
 
         private Duration duration(long amount, TemporalUnit unit) {
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/TrafficShareUpdater.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/TrafficShareUpdater.java
new file mode 100644
index 00000000000..7c95125c6c3
--- /dev/null
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/TrafficShareUpdater.java
@@ -0,0 +1,66 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.controller.maintenance;
+
+import com.yahoo.config.provision.SystemName;
+import com.yahoo.vespa.hosted.controller.ApplicationController;
+import com.yahoo.vespa.hosted.controller.Controller;
+import com.yahoo.vespa.hosted.controller.Instance;
+import com.yahoo.vespa.hosted.controller.api.integration.configserver.NodeRepository;
+import com.yahoo.vespa.hosted.controller.application.Deployment;
+
+import java.time.Duration;
+
+/**
+ * This computes, for every application deployment
+ * - the current fraction of the application's global traffic it receives
+ * - the max fraction it can possibly receive, assuming traffic is evenly distributed over regions
+ *   and max one region is down at any time. (We can let deployment.xml override these assumptions later).
+ *
+ * These two numbers are sent to a config server of each region where it is ultimately
+ * consumed by autoscaling.
+ *
+ * It depends on the traffic metrics collected by DeploymentMetricsMaintainer.
+ *
+ * @author bratseth
+ */
+public class TrafficShareUpdater extends ControllerMaintainer {
+
+    private final ApplicationController applications;
+    private final NodeRepository nodeRepository;
+
+    public TrafficShareUpdater(Controller controller, Duration duration) {
+        super(controller, duration, DeploymentMetricsMaintainer.class.getSimpleName(), SystemName.all());
+        this.applications = controller.applications();
+        this.nodeRepository = controller.serviceRegistry().configServer().nodeRepository();
+    }
+
+    @Override
+    protected boolean maintain() {
+        for (var application : applications.asList()) {
+            for (var instance : application.instances().values()) {
+                for (var deployment : instance.deployments().values()) {
+                    if ( ! deployment.zone().environment().isProduction()) continue;
+                    updateTrafficFraction(instance, deployment);
+                }
+            }
+        }
+        return true;
+    }
+
+    private void updateTrafficFraction(Instance instance, Deployment deployment) {
+        double qpsInZone = deployment.metrics().queriesPerSecond();
+        double totalQps = instance.deployments().values().stream()
+                                                         .filter(i -> i.zone().environment().isProduction())
+                                                         .mapToDouble(i -> i.metrics().queriesPerSecond()).sum();
+        long prodRegions = instance.deployments().values().stream()
+                                                          .filter(i -> i.zone().environment().isProduction())
+                                                          .count();
+        double currentReadShare = totalQps == 0 ? 0 : qpsInZone / totalQps;
+        double maxReadShare = prodRegions < 2 ? 1.0 : 1.0 / ( prodRegions - 1.0);
+        if (currentReadShare > maxReadShare) // This can happen because the assumption of equal traffic
+            maxReadShare = currentReadShare; // distribution can be incorrect
+
+        nodeRepository.patchApplication(deployment.zone(), instance.id(), currentReadShare, maxReadShare);
+    }
+
+}