Load the minimal set of models needed in dev

22 files changed, 258 insertions, 50 deletions

diff --git a/config-model/src/main/java/com/yahoo/config/model/provision/Host.java b/config-model/src/main/java/com/yahoo/config/model/provision/Host.java
index 0374afe4e43..8c8debbae43 100644
--- a/config-model/src/main/java/com/yahoo/config/model/provision/Host.java
+++ b/config-model/src/main/java/com/yahoo/config/model/provision/Host.java
@@ -2,6 +2,7 @@
 package com.yahoo.config.model.provision;
 
 import com.google.common.collect.ImmutableList;
+import com.yahoo.component.Version;
 import com.yahoo.config.provision.Flavor;
 
 import java.util.ArrayList;
@@ -18,6 +19,7 @@ public class Host {
     private final String hostname;
     private final ImmutableList<String> aliases;
     private final Optional<Flavor> flavor;
+    private final Optional<Version> version;
 
     public Host(String hostname) {
         this(hostname, ImmutableList.of(), Optional.empty());
@@ -28,9 +30,14 @@ public class Host {
     }
 
     public Host(String hostname, List<String> hostAliases, Optional<Flavor> flavor) {
+        this(hostname, hostAliases, flavor, Optional.empty());
+    }
+
+    public Host(String hostname, List<String> hostAliases, Optional<Flavor> flavor, Optional<Version> version) {
         this.hostname = hostname;
         this.aliases = ImmutableList.copyOf(hostAliases);
         this.flavor = flavor;
+        this.version = version;
     }
 
     public String hostname() { return hostname; }
@@ -40,6 +47,9 @@ public class Host {
 
     public Optional<Flavor> flavor() { return flavor; }
 
+    /** The current Vespa version running on this host, or empty if not known */
+    public Optional<Version> version() { return version; }
+
     @Override
     public String toString() {
         return hostname + (aliases.size() > 0 ? " (aliases: " + aliases + ")" : "" ) +
diff --git a/config-model/src/main/java/com/yahoo/config/model/provision/InMemoryProvisioner.java b/config-model/src/main/java/com/yahoo/config/model/provision/InMemoryProvisioner.java
index 2e1d507eea1..e6b89d7f390 100644
--- a/config-model/src/main/java/com/yahoo/config/model/provision/InMemoryProvisioner.java
+++ b/config-model/src/main/java/com/yahoo/config/model/provision/InMemoryProvisioner.java
@@ -103,7 +103,7 @@ public class InMemoryProvisioner implements HostProvisioner {
         List<Host> defaultHosts = freeNodes.get("default");
         if (defaultHosts.isEmpty()) throw new IllegalArgumentException("No more hosts of default flavor available");
         Host newHost = freeNodes.removeValue("default", 0);
-        HostSpec hostSpec = new HostSpec(newHost.hostname(), newHost.aliases(), newHost.flavor(), Optional.empty());
+        HostSpec hostSpec = new HostSpec(newHost.hostname(), newHost.aliases(), newHost.flavor(), Optional.empty(), newHost.version());
         legacyMapping.put(alias, hostSpec);
         return hostSpec;
     }
@@ -148,7 +148,11 @@ public class InMemoryProvisioner implements HostProvisioner {
     }
 
     private HostSpec retire(HostSpec host) {
-        return new HostSpec(host.hostname(), host.aliases(), host.membership().get().retire());
+        return new HostSpec(host.hostname(),
+                            host.aliases(),
+                            host.flavor(),
+                            Optional.of(host.membership().get().retire()),
+                            host.version());
     }
 
     private List<HostSpec> allocateHostGroup(ClusterSpec clusterGroup, String flavor, int nodesInGroup, int startIndex) {
@@ -160,7 +164,7 @@ public class InMemoryProvisioner implements HostProvisioner {
             if (freeNodes.get(flavor).isEmpty()) throw new IllegalArgumentException("Insufficient capacity of flavor '" + flavor + "'");
             Host newHost = freeNodes.removeValue(flavor, 0);
             ClusterMembership membership = ClusterMembership.from(clusterGroup, nextIndex++);
-            allocation.add(new HostSpec(newHost.hostname(), newHost.aliases(), newHost.flavor(), Optional.of(membership)));
+            allocation.add(new HostSpec(newHost.hostname(), newHost.aliases(), newHost.flavor(), Optional.of(membership), newHost.version()));
         }
         nextIndexInCluster.put(new Pair<>(clusterGroup.type(), clusterGroup.id()), nextIndex);
 
diff --git a/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java b/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
index 99c079739b4..0af11fdb941 100644
--- a/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
+++ b/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
@@ -14,7 +14,6 @@ import java.util.List;
  * application if one exists.
  *
  * @author hmusum
- * @since 5.11
  */
 public class SingleNodeProvisioner implements HostProvisioner {
 
diff --git a/config-model/src/main/java/com/yahoo/vespa/model/HostResource.java b/config-model/src/main/java/com/yahoo/vespa/model/HostResource.java
index 0f7c040bf02..5c5bbba301f 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/HostResource.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/HostResource.java
@@ -1,6 +1,7 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.model;
 
+import com.yahoo.component.Version;
 import com.yahoo.config.model.api.HostInfo;
 import com.yahoo.config.provision.ClusterMembership;
 import com.yahoo.config.provision.Flavor;
@@ -44,13 +45,21 @@ public class HostResource implements Comparable<HostResource> {
     // Empty for self-hosted Vespa.
     private Optional<Flavor> flavor = Optional.empty();
 
+    /** The current Vespa version running on this node, or empty if not known */
+    private final Optional<Version> version;
+
     /**
      * Create a new {@link HostResource} bound to a specific {@link com.yahoo.vespa.model.Host}.
      *
      * @param host {@link com.yahoo.vespa.model.Host} object to bind to.
      */
     public HostResource(Host host) {
+        this(host, Optional.empty());
+    }
+
+    public HostResource(Host host, Optional<Version> version) {
         this.host = host;
+        this.version = version;
     }
 
     /**
@@ -59,6 +68,9 @@ public class HostResource implements Comparable<HostResource> {
      */
     public Host getHost() { return host; }
 
+    /** Returns the current Vespa version running on this node, or null if not known */
+    public Optional<Version> version() { return version; }
+
     /**
      * Returns the baseport of the first available port range of length numPorts,
      * or 0 if there is no range of that length available.
diff --git a/config-model/src/main/java/com/yahoo/vespa/model/HostSystem.java b/config-model/src/main/java/com/yahoo/vespa/model/HostSystem.java
index 6ef6c208c0a..5f55755c5a4 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/HostSystem.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/HostSystem.java
@@ -111,7 +111,7 @@ public class HostSystem extends AbstractConfigProducer<Host> {
 
     private HostResource addNewHost(HostSpec hostSpec) {
         Host host = new Host(this, hostSpec.hostname());
-        HostResource hostResource = new HostResource(host);
+        HostResource hostResource = new HostResource(host, hostSpec.version());
         hostResource.setFlavor(hostSpec.flavor());
         hostSpec.membership().ifPresent(hostResource::addClusterMembership);
         hostname2host.put(host.getHostname(), hostResource);
@@ -162,7 +162,7 @@ public class HostSystem extends AbstractConfigProducer<Host> {
     Set<HostSpec> getHostSpecs() {
         return getHosts().stream()
                 .map(host -> new HostSpec(host.getHostname(), Collections.emptyList(),
-                                          host.getFlavor(), host.primaryClusterMembership()))
+                                          host.getFlavor(), host.primaryClusterMembership(), host.version()))
                 .collect(Collectors.toCollection(LinkedHashSet::new));
     }
 
diff --git a/config-provisioning/src/main/java/com/yahoo/config/provision/AllocatedHosts.java b/config-provisioning/src/main/java/com/yahoo/config/provision/AllocatedHosts.java
index 13efc2b3337..cc343821e0b 100644
--- a/config-provisioning/src/main/java/com/yahoo/config/provision/AllocatedHosts.java
+++ b/config-provisioning/src/main/java/com/yahoo/config/provision/AllocatedHosts.java
@@ -29,8 +29,13 @@ public class AllocatedHosts {
     private static final String hostSpecHostName = "hostName";
     private static final String hostSpecMembership = "membership";
     private static final String hostSpecFlavor = "flavor";
+
+    /** Wanted version */
     private static final String hostSpecVespaVersion = "vespaVersion";
 
+    /** Current version */
+    private static final String hostSpecCurrentVespaVersion = "currentVespaVersion";
+
     private final ImmutableSet<HostSpec> hosts;
 
     AllocatedHosts(Set<HostSpec> hosts) {
@@ -49,12 +54,12 @@ public class AllocatedHosts {
 
     private void toSlime(HostSpec host, Cursor cursor) {
         cursor.setString(hostSpecHostName, host.hostname());
-        if (host.membership().isPresent()) {
-            cursor.setString(hostSpecMembership, host.membership().get().stringValue());
-            cursor.setString(hostSpecVespaVersion, host.membership().get().cluster().vespaVersion().toString());
-        }
-        if (host.flavor().isPresent())
-            cursor.setString(hostSpecFlavor, host.flavor().get().name());
+        host.membership().ifPresent(membership -> {
+            cursor.setString(hostSpecMembership, membership.stringValue());
+            cursor.setString(hostSpecVespaVersion, membership.cluster().vespaVersion().toString());
+        });
+        host.flavor().ifPresent(flavor -> cursor.setString(hostSpecFlavor, flavor.name()));
+        host.version().ifPresent(version -> cursor.setString(hostSpecCurrentVespaVersion, version.toString()));
     }
 
     /** Returns the hosts of this allocation */
@@ -66,19 +71,21 @@ public class AllocatedHosts {
         array.traverse(new ArrayTraverser() {
             @Override
             public void entry(int i, Inspector inspector) {
-                hosts.add(hostsFromSlime(inspector.field(hostSpecKey), nodeFlavors));
+                hosts.add(hostFromSlime(inspector.field(hostSpecKey), nodeFlavors));
             }
         });
         return new AllocatedHosts(hosts);
     }
 
-    static HostSpec hostsFromSlime(Inspector object, Optional<NodeFlavors> nodeFlavors) {
+    static HostSpec hostFromSlime(Inspector object, Optional<NodeFlavors> nodeFlavors) {
         Optional<ClusterMembership> membership =
                 object.field(hostSpecMembership).valid() ? Optional.of(membershipFromSlime(object)) : Optional.empty();
         Optional<Flavor> flavor =
                 object.field(hostSpecFlavor).valid() ? flavorFromSlime(object, nodeFlavors) : Optional.empty();
+        Optional<com.yahoo.component.Version> version =
+                optionalString(object.field(hostSpecCurrentVespaVersion)).map(com.yahoo.component.Version::new);
 
-        return new HostSpec(object.field(hostSpecHostName).asString(),Collections.emptyList(), flavor, membership);
+        return new HostSpec(object.field(hostSpecHostName).asString(), Collections.emptyList(), flavor, membership, version);
     }
 
     private static ClusterMembership membershipFromSlime(Inspector object) {
@@ -91,6 +98,11 @@ public class AllocatedHosts {
                 .orElse(Optional.empty());
     }
 
+    private static Optional<String> optionalString(Inspector inspector) {
+        if ( ! inspector.valid()) return Optional.empty();
+        return Optional.of(inspector.asString());
+    }
+
     public byte[] toJson() throws IOException {
         Slime slime = new Slime();
         toSlime(slime.setObject());
diff --git a/config-provisioning/src/main/java/com/yahoo/config/provision/ClusterSpec.java b/config-provisioning/src/main/java/com/yahoo/config/provision/ClusterSpec.java
index a0df2547631..837e062e356 100644
--- a/config-provisioning/src/main/java/com/yahoo/config/provision/ClusterSpec.java
+++ b/config-provisioning/src/main/java/com/yahoo/config/provision/ClusterSpec.java
@@ -38,6 +38,7 @@ public final class ClusterSpec {
     /** Returns the cluster id */
     public Id id() { return id; }
 
+    /** Returns the version of Vespa that we want this cluster to run */
     public Version vespaVersion() { return vespaVersion; }
 
     /** Returns the group within the cluster this specifies, or empty to specify the whole cluster */
diff --git a/config-provisioning/src/main/java/com/yahoo/config/provision/HostSpec.java b/config-provisioning/src/main/java/com/yahoo/config/provision/HostSpec.java
index dd8bc311939..a6607092d8e 100644
--- a/config-provisioning/src/main/java/com/yahoo/config/provision/HostSpec.java
+++ b/config-provisioning/src/main/java/com/yahoo/config/provision/HostSpec.java
@@ -27,14 +27,21 @@ public class HostSpec implements Comparable<HostSpec> {
 
     private final Optional<Flavor> flavor;
 
+    private final Optional<com.yahoo.component.Version> version;
+
     public HostSpec(String hostname, Optional<ClusterMembership> membership) {
         this(hostname, new ArrayList<>(), Optional.empty(), membership);
     }
 
+    // TODO: Remove after May 2018
     public HostSpec(String hostname, ClusterMembership membership, Flavor flavor) {
         this(hostname, new ArrayList<>(), Optional.of(flavor), Optional.of(membership));
     }
 
+    public HostSpec(String hostname, ClusterMembership membership, Flavor flavor, Optional<com.yahoo.component.Version> version) {
+        this(hostname, new ArrayList<>(), Optional.of(flavor), Optional.of(membership), version);
+    }
+
     public HostSpec(String hostname, List<String> aliases) {
         this(hostname, aliases, Optional.empty(), Optional.empty());
     }
@@ -44,11 +51,18 @@ public class HostSpec implements Comparable<HostSpec> {
     }
 
     public HostSpec(String hostname, List<String> aliases, Optional<Flavor> flavor, Optional<ClusterMembership> membership) {
+        this(hostname, aliases, flavor, membership, Optional.empty());
+    }
+
+    public HostSpec(String hostname, List<String> aliases, Optional<Flavor> flavor,
+                    Optional<ClusterMembership> membership, Optional<com.yahoo.component.Version> version) {
         if (hostname == null || hostname.isEmpty()) throw new IllegalArgumentException("Hostname must be specified");
+        Objects.requireNonNull(version, "Version cannot be null but can be empty");
         this.hostname = hostname;
         this.aliases = ImmutableList.copyOf(aliases);
         this.flavor = flavor;
         this.membership = membership;
+        this.version = version;
     }
 
     /** Returns the name identifying this host */
@@ -59,6 +73,9 @@ public class HostSpec implements Comparable<HostSpec> {
 
     public Optional<Flavor> flavor() { return flavor; }
 
+    /** Returns the current version of Vespa running on this node, or empty if not known */
+    public Optional<com.yahoo.component.Version> version() { return version; }
+
     /** Returns the membership of this host, or an empty value if not present */
     public Optional<ClusterMembership> membership() { return membership; }
 
diff --git a/config-provisioning/src/main/java/com/yahoo/config/provision/ProvisionInfo.java b/config-provisioning/src/main/java/com/yahoo/config/provision/ProvisionInfo.java
index 8444f2e10fc..ca8d531634b 100644
--- a/config-provisioning/src/main/java/com/yahoo/config/provision/ProvisionInfo.java
+++ b/config-provisioning/src/main/java/com/yahoo/config/provision/ProvisionInfo.java
@@ -39,7 +39,7 @@ public class ProvisionInfo extends AllocatedHosts {
         array.traverse(new ArrayTraverser() {
             @Override
             public void entry(int i, Inspector inspector) {
-                hosts.add(hostsFromSlime(inspector.field(hostSpecKey), nodeFlavors));
+                hosts.add(hostFromSlime(inspector.field(hostSpecKey), nodeFlavors));
             }
         });
         return new ProvisionInfo(hosts);
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/ApplicationRepository.java b/configserver/src/main/java/com/yahoo/vespa/config/server/ApplicationRepository.java
index 636ac7e7070..43be4e279f0 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/ApplicationRepository.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/ApplicationRepository.java
@@ -210,7 +210,7 @@ public class ApplicationRepository implements com.yahoo.config.provision.Deploye
     }
 
     private Deployment deployFromPreparedSession(LocalSession session, Tenant tenant, Duration timeout) {
-        return Deployment.prepared(session, this, hostProvisioner, tenant,timeout, clock);
+        return Deployment.prepared(session, this, hostProvisioner, tenant, timeout, clock);
     }
 
     // ---------------- Application operations ----------------------------------------------------------------
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ActivatedModelsBuilder.java b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ActivatedModelsBuilder.java
index 1301f24788f..08fd0a7afda 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ActivatedModelsBuilder.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ActivatedModelsBuilder.java
@@ -49,12 +49,12 @@ public class ActivatedModelsBuilder extends ModelsBuilder<Application> {
     private final ConfigDefinitionRepo configDefinitionRepo;
     private final Metrics metrics;
     private final Curator curator;
-    private final Zone zone;
     private final DeployLogger logger;
 
     public ActivatedModelsBuilder(TenantName tenant, long appGeneration, SessionZooKeeperClient zkClient, GlobalComponentRegistry globalComponentRegistry) {
         super(globalComponentRegistry.getModelFactoryRegistry(), 
-              globalComponentRegistry.getHostProvisioner().isPresent());
+              globalComponentRegistry.getHostProvisioner().isPresent(),
+              globalComponentRegistry.getZone());
         this.tenant = tenant;
         this.appGeneration = appGeneration;
         this.zkClient = zkClient;
@@ -63,7 +63,6 @@ public class ActivatedModelsBuilder extends ModelsBuilder<Application> {
         this.configDefinitionRepo = globalComponentRegistry.getConfigDefinitionRepo();
         this.metrics = globalComponentRegistry.getMetrics();
         this.curator = globalComponentRegistry.getCurator();
-        this.zone = globalComponentRegistry.getZone();
         this.logger = new SilentDeployLogger();
     }
 
@@ -109,7 +108,7 @@ public class ActivatedModelsBuilder extends ModelsBuilder<Application> {
         return createModelContextProperties(
                 applicationId,
                 configserverConfig,
-                zone,
+                zone(),
                 new Rotations(curator, Tenants.getTenantPath(tenant)).readRotationsFromZooKeeper(applicationId));
     }
 
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ModelsBuilder.java b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ModelsBuilder.java
index daff32198a3..04e0c9a2902 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ModelsBuilder.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ModelsBuilder.java
@@ -9,6 +9,7 @@ import com.yahoo.config.model.api.ModelFactory;
 import com.yahoo.config.provision.AllocatedHosts;
 import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.config.provision.ApplicationLockException;
+import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.OutOfCapacityException;
 import com.yahoo.config.provision.Rotation;
@@ -49,11 +50,17 @@ public abstract class ModelsBuilder<MODELRESULT extends ModelResult> {
     /** True if we are running in hosted mode */
     private final boolean hosted;
 
-    protected ModelsBuilder(ModelFactoryRegistry modelFactoryRegistry, boolean hosted) {
+    private final Zone zone;
+
+    protected ModelsBuilder(ModelFactoryRegistry modelFactoryRegistry, boolean hosted, Zone zone) {
         this.modelFactoryRegistry = modelFactoryRegistry;
         this.hosted = hosted;
+        this.zone = zone;
     }
 
+    /** Returns the zone this is running in */
+    protected Zone zone() { return zone; }
+
     /**
      * Builds all applicable model versions
      * 
@@ -137,6 +144,9 @@ public abstract class ModelsBuilder<MODELRESULT extends ModelResult> {
         List<MODELRESULT> allApplicationVersions = new ArrayList<>();
         allApplicationVersions.add(latestModelVersion);
 
+        if (zone().environment() == Environment.dev)
+            versions = keepThoseUsedOn(allocatedHosts.get(), versions);
+
         // TODO: We use the allocated hosts from the newest version when building older model versions.
         // This is correct except for the case where an old model specifies a cluster which the new version
         // does not. In that case we really want to extend the set of allocated hosts to include those of that
@@ -170,6 +180,17 @@ public abstract class ModelsBuilder<MODELRESULT extends ModelResult> {
         return versionList.get(versionList.size() - 1);
     }
 
+    /** Returns the subset of the given versions which are in use on these hosts */
+    private Set<Version> keepThoseUsedOn(AllocatedHosts hosts, Set<Version> versions) {
+        return versions.stream().filter(version -> mayBeUsedOn(hosts, version)).collect(Collectors.toSet());
+    }
+
+    private boolean mayBeUsedOn(AllocatedHosts hosts, Version version) {
+        com.yahoo.component.Version v = new com.yahoo.component.Version(version.toString());
+        return hosts.getHosts().stream()
+                               .anyMatch(host -> ! host.version().isPresent() || host.version().get().equals(v));
+    }
+
     protected abstract MODELRESULT buildModelVersion(ModelFactory modelFactory, ApplicationPackage applicationPackage,
                                                      ApplicationId applicationId, 
                                                      com.yahoo.component.Version wantedNodeVespaVersion,
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/PreparedModelsBuilder.java b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/PreparedModelsBuilder.java
index c265e0f6c2e..d7b84d75b5c 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/PreparedModelsBuilder.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/PreparedModelsBuilder.java
@@ -62,7 +62,7 @@ public class PreparedModelsBuilder extends ModelsBuilder<PreparedModelsBuilder.P
                                  PrepareParams params,
                                  Optional<ApplicationSet> currentActiveApplicationSet,
                                  ModelContext.Properties properties) {
-        super(modelFactoryRegistry, properties.hostedVespa());
+        super(modelFactoryRegistry, properties.hostedVespa(), properties.zone());
         this.permanentApplicationPackage = permanentApplicationPackage;
         this.configDefinitionRepo = configDefinitionRepo;
 
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactory.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactory.java
index 3c05d491b35..172620a643a 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactory.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactory.java
@@ -10,9 +10,9 @@ import java.io.File;
  * A session factory responsible for creating deploy sessions.
  *
  * @author lulf
- * @since 5.1
  */
 public interface SessionFactory {
+
     /**
      * Creates a new deployment session from an application package.
      *
@@ -34,4 +34,5 @@ public interface SessionFactory {
      * @return a new session
      */
     LocalSession createSessionFromExisting(LocalSession existingSession, DeployLogger logger, TimeoutBudget timeoutBudget);
+
 }
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactoryImpl.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactoryImpl.java
index fdc681b5fb6..9bbaf35bce9 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactoryImpl.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionFactoryImpl.java
@@ -33,8 +33,7 @@ import java.util.logging.Logger;
  * Serves as the factory of sessions. Takes care of copying files to the correct folder and initializing the
  * session state.
  *
- * @author lulf
- * @since 5.1
+ * @author Ulf Lilleengen
  */
 public class SessionFactoryImpl implements SessionFactory, LocalSessionLoader {
 
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
index f7d6b8f05fe..de903b7f2dd 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
@@ -210,6 +210,7 @@ public class SessionZooKeeperClient {
 
     /**
      * Create necessary paths atomically for a new session.
+     *
      * @param createTime Time of session creation.
      * @param timeUnit Time unit of createTime.
      */
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/TestComponentRegistry.java b/configserver/src/test/java/com/yahoo/vespa/config/server/TestComponentRegistry.java
index 3b56b5b35bf..d026989a43e 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/TestComponentRegistry.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/TestComponentRegistry.java
@@ -30,8 +30,7 @@ import java.util.Optional;
 import static com.yahoo.vespa.config.server.SuperModelRequestHandlerTest.emptyNodeFlavors;
 
 /**
- * @author lulf
- * @since 5.1
+ * @author Ulf Lilleengen
  */
 public class TestComponentRegistry implements GlobalComponentRegistry {
 
@@ -50,6 +49,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
     private final FileDistributionFactory fileDistributionFactory;
     private final ModelFactoryRegistry modelFactoryRegistry;
     private final Optional<Provisioner> hostProvisioner;
+    private final Zone zone;
     private final Clock clock;
 
     private TestComponentRegistry(Curator curator, ConfigCurator configCurator, Metrics metrics,
@@ -65,6 +65,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
                                   ConfigDefinitionRepo defRepo,
                                   ReloadListener reloadListener,
                                   TenantListener tenantListener,
+                                  Zone zone,
                                   Clock clock) {
         this.curator = curator;
         this.configCurator = configCurator;
@@ -81,6 +82,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
         this.modelFactoryRegistry = modelFactoryRegistry;
         this.hostProvisioner = hostProvisioner;
         this.sessionPreparer = sessionPreparer;
+        this.zone = zone;
         this.clock = clock;
     }
 
@@ -101,6 +103,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
         private Optional<FileDistributionFactory> fileDistributionFactory = Optional.empty();
         private ModelFactoryRegistry modelFactoryRegistry = new ModelFactoryRegistry(Collections.singletonList(new VespaModelFactory(new NullConfigModelRegistry())));
         private Optional<Provisioner> hostProvisioner = Optional.empty();
+        private Zone zone = Zone.defaultZone();
         private Clock clock = Clock.systemUTC();
 
         public Builder configServerConfig(ConfigserverConfig configserverConfig) {
@@ -138,6 +141,11 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
             return this;
         }
 
+        public Builder zone(Zone zone) {
+            this.zone = zone;
+            return this;
+        }
+
         public Builder clock(Clock clock) {
             this.clock = clock;
             return this;
@@ -154,7 +162,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
             SessionPreparer sessionPreparer = new SessionPreparer(modelFactoryRegistry, fileDistributionFactory,
                                                                   hostProvisionerProvider, permApp,
                                                                   configserverConfig, defRepo, curator,
-                                                                  new Zone(configserverConfig, emptyNodeFlavors()));
+                                                                  zone);
             return new TestComponentRegistry(curator, configCurator.orElse(ConfigCurator.create(curator)),
                                              metrics, modelFactoryRegistry,
                                              permApp,
@@ -163,7 +171,7 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
                                              new ConfigServerDB(configserverConfig),
                                              hostRegistries, configserverConfig, sessionPreparer,
                                              hostProvisioner, defRepo, reloadListener,
-                                             tenantListener, clock);
+                                             tenantListener, zone, clock);
         }
     }
 
@@ -193,19 +201,17 @@ public class TestComponentRegistry implements GlobalComponentRegistry {
     public HostRegistries getHostRegistries() { return hostRegistries;}
     @Override
     public ModelFactoryRegistry getModelFactoryRegistry() { return modelFactoryRegistry; }
-
     @Override
     public Optional<Provisioner> getHostProvisioner() {
         return hostProvisioner;
     }
-
     @Override
     public Zone getZone() {
-        return Zone.defaultZone();
+        return zone;
     }
+    @Override
+    public Clock getClock() { return clock;}
 
     public FileDistributionFactory getFileDistributionFactory() { return fileDistributionFactory; }
 
-    @Override
-    public Clock getClock() { return clock;}
 }
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/DeployTester.java b/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/DeployTester.java
index 95cfd17139d..2a57d85f3f7 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/DeployTester.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/DeployTester.java
@@ -25,6 +25,7 @@ import com.yahoo.config.provision.ProvisionLogger;
 import com.yahoo.config.provision.Provisioner;
 import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.Version;
+import com.yahoo.config.provision.Zone;
 import com.yahoo.transaction.NestedTransaction;
 import com.yahoo.vespa.config.server.ApplicationRepository;
 import com.yahoo.vespa.config.server.TestComponentRegistry;
@@ -91,9 +92,18 @@ public class DeployTester {
     }
 
     public DeployTester(String appPath, List<ModelFactory> modelFactories, ConfigserverConfig configserverConfig, Clock clock) {
+        this(appPath, modelFactories, configserverConfig, clock, Zone.defaultZone());
+    }
+
+    public DeployTester(String appPath, List<ModelFactory> modelFactories, ConfigserverConfig configserverConfig, Clock clock, Zone zone) {
+        this(appPath, modelFactories, configserverConfig, clock, Zone.defaultZone(), createProvisioner());
+    }
+
+    public DeployTester(String appPath, List<ModelFactory> modelFactories, ConfigserverConfig configserverConfig, Clock clock, Zone zone, HostProvisioner provisioner) {
         this.clock = clock;
         TestComponentRegistry componentRegistry = createComponentRegistry(new MockCurator(), Metrics.createTestMetrics(),
-                                                                          modelFactories, configserverConfig, clock);
+                                                                          modelFactories, configserverConfig, clock, zone,
+                                                                          provisioner);
         try {
             this.testApp = new File(appPath);
             this.tenants = new Tenants(componentRegistry, Collections.emptySet());
@@ -102,7 +112,7 @@ public class DeployTester {
         catch (Exception e) {
             throw new IllegalArgumentException(e);
         }
-        applicationRepository = new ApplicationRepository(tenants, createHostProvisioner(), clock);
+        applicationRepository = new ApplicationRepository(tenants, new ProvisionerAdapter(provisioner), clock);
     }
 
     public Tenant tenant() {
@@ -110,13 +120,13 @@ public class DeployTester {
     }
     
     /** Create a model factory for the version of this source*/
-    public static ModelFactory createModelFactory(Clock clock) { 
-        return new VespaModelFactory(new NullConfigModelRegistry(), clock);
+    public static CountingModelFactory createModelFactory(Clock clock) {
+        return new CountingModelFactory(clock);
     }
 
     /** Create a model factory for a particular version */
-    public static ModelFactory createModelFactory(Version version, Clock clock) { 
-        return new VespaModelFactory(version, new NullConfigModelRegistry(), clock); 
+    public static CountingModelFactory createModelFactory(Version version, Clock clock) {
+        return new CountingModelFactory(version, clock);
     }
 
     /** Create a model factory which always fails validation */
@@ -168,24 +178,26 @@ public class DeployTester {
         return applicationRepository;
     }
 
-    private Provisioner createHostProvisioner() {
-        return new ProvisionerAdapter(new InMemoryProvisioner(true, "host0", "host1", "host2", "host3", "host4", "host5"));
+    private static HostProvisioner createProvisioner() {
+        return new InMemoryProvisioner(true, "host0", "host1", "host2", "host3", "host4", "host5");
     }
 
     private TestComponentRegistry createComponentRegistry(Curator curator, Metrics metrics,
                                                           List<ModelFactory> modelFactories,
                                                           ConfigserverConfig configserverConfig,
-                                                          Clock clock) {
+                                                          Clock clock,
+                                                          Zone zone,
+                                                          HostProvisioner provisioner) {
         TestComponentRegistry.Builder builder = new TestComponentRegistry.Builder();
 
-        if (configserverConfig.hostedVespa()) {
-            builder.provisioner(createHostProvisioner());
-        }
+        if (configserverConfig.hostedVespa())
+            builder.provisioner(new ProvisionerAdapter(provisioner));
 
         builder.configServerConfig(configserverConfig)
                .curator(curator)
                .modelFactoryRegistry(new ModelFactoryRegistry(modelFactories))
                .metrics(metrics)
+               .zone(zone)
                .clock(clock);
         return builder.build();
     }
@@ -252,4 +264,40 @@ public class DeployTester {
 
     }
 
+    /** A wrapper of the regular model factory which counts the number of models it has created */
+    public static class CountingModelFactory implements ModelFactory {
+
+        private final VespaModelFactory wrapped;
+        private int creationCount;
+
+        public CountingModelFactory(Clock clock) {
+            this.wrapped = new VespaModelFactory(new NullConfigModelRegistry(), clock);
+        }
+
+        public CountingModelFactory(Version version, Clock clock) {
+            this.wrapped = new VespaModelFactory(version, new NullConfigModelRegistry(), clock);
+        }
+
+        /** Returns the number of models created successfully by this instance */
+        public int creationCount() { return creationCount; }
+
+        @Override
+        public Version getVersion() { return wrapped.getVersion(); }
+
+        @Override
+        public Model createModel(ModelContext modelContext) {
+            Model model = wrapped.createModel(modelContext);
+            creationCount++;
+            return model;
+        }
+
+        @Override
+        public ModelCreateResult createAndValidateModel(ModelContext modelContext, boolean ignoreValidationErrors) {
+            ModelCreateResult result = wrapped.createAndValidateModel(modelContext, ignoreValidationErrors);
+            creationCount++;
+            return result;
+        }
+
+    }
+
 }
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/HostedDeployTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/HostedDeployTest.java
index bd9c6476ad6..8271d6de452 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/HostedDeployTest.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/deploy/HostedDeployTest.java
@@ -4,14 +4,22 @@ package com.yahoo.vespa.config.server.deploy;
 import com.google.common.io.Files;
 import com.yahoo.cloud.config.ConfigserverConfig;
 import com.yahoo.config.model.api.ModelFactory;
+import com.yahoo.config.model.provision.Host;
+import com.yahoo.config.model.provision.Hosts;
+import com.yahoo.config.model.provision.InMemoryProvisioner;
 import com.yahoo.config.provision.ApplicationId;
+import com.yahoo.config.provision.Environment;
+import com.yahoo.config.provision.RegionName;
 import com.yahoo.config.provision.Version;
+import com.yahoo.config.provision.Zone;
 import com.yahoo.test.ManualClock;
+import static com.yahoo.vespa.config.server.deploy.DeployTester.CountingModelFactory;
 import org.junit.Test;
 
 import java.time.Duration;
 import java.time.Instant;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 
@@ -54,9 +62,47 @@ public class HostedDeployTest {
         modelFactories.add(DeployTester.createModelFactory(Version.fromString("6.1.0"), clock));
         modelFactories.add(DeployTester.createModelFactory(Version.fromString("6.2.0"), clock));
         modelFactories.add(DeployTester.createModelFactory(Version.fromString("7.0.0"), clock));
-        DeployTester tester = new DeployTester("src/test/apps/hosted/", modelFactories, createConfigserverConfig());
+        DeployTester tester = new DeployTester("src/test/apps/hosted/", modelFactories, createConfigserverConfig(), clock, Zone.defaultZone());
         ApplicationId app = tester.deployApp("myApp", Instant.now());
         assertEquals(3, tester.getAllocatedHostsOf(app).getHosts().size());
+
+    }
+
+    /** Test that unused versions are skipped in dev */
+    @Test
+    public void testDeployMultipleVersionsInDev() {
+        List<Host> hosts = new ArrayList<>();
+        hosts.add(createHost("host1", "6.0.0"));
+        hosts.add(createHost("host2", "6.0.2"));
+        hosts.add(createHost("host3", "7.1.0"));
+        InMemoryProvisioner provisioner = new InMemoryProvisioner(new Hosts(hosts), true);
+        ManualClock clock = new ManualClock("2016-10-09T00:00:00");
+
+        CountingModelFactory factory600 = DeployTester.createModelFactory(Version.fromString("6.0.0"), clock);
+        CountingModelFactory factory610 = DeployTester.createModelFactory(Version.fromString("6.1.0"), clock);
+        CountingModelFactory factory620 = DeployTester.createModelFactory(Version.fromString("6.2.0"), clock);
+        CountingModelFactory factory700 = DeployTester.createModelFactory(Version.fromString("7.0.0"), clock);
+        CountingModelFactory factory710 = DeployTester.createModelFactory(Version.fromString("7.1.0"), clock);
+        CountingModelFactory factory720 = DeployTester.createModelFactory(Version.fromString("7.2.0"), clock);
+        List<ModelFactory> modelFactories = new ArrayList<>();
+        modelFactories.add(factory600);
+        modelFactories.add(factory610);
+        modelFactories.add(factory620);
+        modelFactories.add(factory700);
+        modelFactories.add(factory710);
+        modelFactories.add(factory720);
+
+        DeployTester tester = new DeployTester("src/test/apps/hosted/", modelFactories, createConfigserverConfig(),
+                                               clock, new Zone(Environment.dev, RegionName.defaultName()), provisioner);
+        ApplicationId app = tester.deployApp("myApp", Instant.now());
+        assertEquals(3, tester.getAllocatedHostsOf(app).getHosts().size());
+
+        assertEquals(1, factory600.creationCount());
+        assertEquals(0, factory610.creationCount());
+        assertEquals(1, factory620.creationCount());
+        assertEquals(0, factory700.creationCount());
+        assertEquals(1, factory710.creationCount());
+        assertEquals("Newest is always included", 1, factory720.creationCount());
     }
 
     @Test
@@ -107,4 +153,8 @@ public class HostedDeployTest {
                                               .multitenant(true));
     }
 
+    private Host createHost(String hostname, String version) {
+        return new Host(hostname, Collections.emptyList(), Optional.empty(), Optional.of(com.yahoo.component.Version.fromString(version)));
+    }
+
 }
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/zookeeper/ZKApplicationPackageTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/zookeeper/ZKApplicationPackageTest.java
index 56ef3f340e2..f0c74d19af9 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/zookeeper/ZKApplicationPackageTest.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/zookeeper/ZKApplicationPackageTest.java
@@ -34,7 +34,8 @@ public class ZKApplicationPackageTest extends TestWithCurator {
     private static final String TEST_FLAVOR_NAME = "test-flavor";
     private static final Optional<Flavor> TEST_FLAVOR = new MockNodeFlavors().getFlavor(TEST_FLAVOR_NAME);
     private static final AllocatedHosts ALLOCATED_HOSTS = AllocatedHosts.withHosts(
-            Collections.singleton(new HostSpec("foo.yahoo.com", Collections.emptyList(), TEST_FLAVOR, Optional.empty())));
+            Collections.singleton(new HostSpec("foo.yahoo.com", Collections.emptyList(), TEST_FLAVOR, Optional.empty(),
+                                               Optional.of(com.yahoo.component.Version.fromString("6.0.1")))));
 
     @Rule
     public TemporaryFolder tmpDir = new TemporaryFolder();
@@ -67,6 +68,7 @@ public class ZKApplicationPackageTest extends TestWithCurator {
         AllocatedHosts readInfo = zkApp.getAllocatedHosts().get();
         assertThat(Utf8.toString(readInfo.toJson()), is(Utf8.toString(ALLOCATED_HOSTS.toJson())));
         assertThat(readInfo.getHosts().iterator().next().flavor(), is(TEST_FLAVOR));
+        assertEquals("6.0.1", readInfo.getHosts().iterator().next().version().get().toString());
         assertTrue(zkApp.getDeployment().isPresent());
         assertThat(DeploymentSpec.fromXml(zkApp.getDeployment().get()).globalServiceId().get(), is("mydisc"));
     }
diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/NodeRepositoryProvisioner.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/NodeRepositoryProvisioner.java
index 304c867a886..3fa70b3242f 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/NodeRepositoryProvisioner.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/NodeRepositoryProvisioner.java
@@ -123,7 +123,8 @@ public class NodeRepositoryProvisioner implements Provisioner {
             log.log(LogLevel.DEBUG, () -> "Prepared node " + node.hostname() + " - " + node.flavor());
             hosts.add(new HostSpec(node.hostname(),
                                    node.allocation().orElseThrow(IllegalStateException::new).membership(),
-                                   node.flavor()));
+                                   node.flavor(),
+                                   node.status().vespaVersion()));
         }
         return hosts;
     }
diff --git a/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTest.java b/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTest.java
index e00f058efaa..2ffe23cea07 100644
--- a/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTest.java
+++ b/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTest.java
@@ -140,6 +140,31 @@ public class ProvisioningTest {
     }
 
     @Test
+    public void nodeVersionIsReturnedIfSet() {
+        ProvisioningTester tester = new ProvisioningTester(new Zone(Environment.dev, RegionName.from("us-east")));
+
+        ApplicationId application1 = tester.makeApplicationId();
+
+        tester.makeReadyNodes(4, "default");
+
+        // deploy
+        SystemState state1 = prepare(application1, 1, 1, 1, 1, "default", tester);
+        tester.activate(application1, state1.allHosts);
+
+        HostSpec host1 = state1.container0.iterator().next();
+        assertFalse(host1.version().isPresent());
+        Node node1 = tester.nodeRepository().getNode(host1.hostname()).get();
+        tester.nodeRepository().write(node1.with(node1.status().withVespaVersion(Version.fromString("1.2.3"))));
+
+        // redeploy
+        SystemState state2 = prepare(application1, 1, 1, 1, 1, "default", tester);
+        tester.activate(application1, state2.allHosts);
+
+        host1 = state2.container0.iterator().next();
+        assertEquals(Version.fromString("1.2.3"), host1.version().get());
+    }
+
+    @Test
     public void application_deployment_variable_application_size() {
         ProvisioningTester tester = new ProvisioningTester(new Zone(Environment.prod, RegionName.from("us-east")));