Add config and feature flag for the number of distributor stripes.

7 files changed, 53 insertions, 5 deletions

diff --git a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
index 92e8c630c7b..7f620a7bd0b 100644
--- a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
+++ b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
@@ -92,6 +92,7 @@ public interface ModelContext {
         @ModelFeatureFlag(owners = {"hmusum"}) default String jvmOmitStackTraceInFastThrowOption(ClusterSpec.Type type) { return ""; }
         @ModelFeatureFlag(owners = {"bjorncs", "jonmv"}) default boolean enableJdiscHttp2() { return false; }
         @ModelFeatureFlag(owners = {"tokle", "bjorncs"}) default boolean enableCustomAclMapping() { return false; }
+        @ModelFeatureFlag(owners = {"geirst", "vekterli"}) default int numDistributorStripes() { return 0; }
     }
 
     /** Warning: As elsewhere in this package, do not make backwards incompatible changes that will break old config models! */
diff --git a/config-model/src/main/java/com/yahoo/config/model/deploy/TestProperties.java b/config-model/src/main/java/com/yahoo/config/model/deploy/TestProperties.java
index 1402f728c73..3722876a53f 100644
--- a/config-model/src/main/java/com/yahoo/config/model/deploy/TestProperties.java
+++ b/config-model/src/main/java/com/yahoo/config/model/deploy/TestProperties.java
@@ -61,6 +61,7 @@ public class TestProperties implements ModelContext.Properties, ModelContext.Fea
     private int maxActivationInhibitedOutOfSyncGroups = 0;
     private List<TenantSecretStore> tenantSecretStores = Collections.emptyList();
     private String jvmOmitStackTraceInFastThrowOption;
+    private int numDistributorStripes = 0;
 
     @Override public ModelContext.FeatureFlags featureFlags() { return this; }
     @Override public boolean multitenant() { return multitenant; }
@@ -102,6 +103,7 @@ public class TestProperties implements ModelContext.Properties, ModelContext.Fea
     @Override public int maxActivationInhibitedOutOfSyncGroups() { return maxActivationInhibitedOutOfSyncGroups; }
     @Override public List<TenantSecretStore> tenantSecretStores() { return tenantSecretStores; }
     @Override public String jvmOmitStackTraceInFastThrowOption(ClusterSpec.Type type) { return jvmOmitStackTraceInFastThrowOption; }
+    @Override public int numDistributorStripes() { return numDistributorStripes; }
 
     public TestProperties setFeedConcurrency(double feedConcurrency) {
         this.feedConcurrency = feedConcurrency;
@@ -248,6 +250,11 @@ public class TestProperties implements ModelContext.Properties, ModelContext.Fea
         return this;
     }
 
+    public TestProperties setNumDistributorStripes(int value) {
+        this.numDistributorStripes = value;
+        return this;
+    }
+
     public static class Spec implements ConfigServerSpec {
 
         private final String hostName;
diff --git a/config-model/src/main/java/com/yahoo/vespa/model/content/DistributorCluster.java b/config-model/src/main/java/com/yahoo/vespa/model/content/DistributorCluster.java
index 0e3fee5a749..390c939c4b4 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/content/DistributorCluster.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/content/DistributorCluster.java
@@ -43,6 +43,7 @@ public class DistributorCluster extends AbstractConfigProducer<Distributor> impl
     private final boolean hasIndexedDocumentType;
     private final boolean useThreePhaseUpdates;
     private final int maxActivationInhibitedOutOfSyncGroups;
+    private final int numDistributorStripes;
 
     public static class Builder extends VespaDomBuilder.DomConfigProducerBuilder<DistributorCluster> {
 
@@ -105,18 +106,20 @@ public class DistributorCluster extends AbstractConfigProducer<Distributor> impl
             final boolean hasIndexedDocumentType = clusterContainsIndexedDocumentType(documentsNode);
             boolean useThreePhaseUpdates = deployState.getProperties().featureFlags().useThreePhaseUpdates();
             int maxInhibitedGroups = deployState.getProperties().featureFlags().maxActivationInhibitedOutOfSyncGroups();
+            int numDistributorStripes = deployState.getProperties().featureFlags().numDistributorStripes();
 
             return new DistributorCluster(parent,
                     new BucketSplitting.Builder().build(new ModelElement(producerSpec)), gc,
                     hasIndexedDocumentType, useThreePhaseUpdates,
-                    maxInhibitedGroups);
+                    maxInhibitedGroups, numDistributorStripes);
         }
     }
 
     private DistributorCluster(ContentCluster parent, BucketSplitting bucketSplitting,
                                GcOptions gc, boolean hasIndexedDocumentType,
                                boolean useThreePhaseUpdates,
-                               int maxActivationInhibitedOutOfSyncGroups)
+                               int maxActivationInhibitedOutOfSyncGroups,
+                               int numDistributorStripes)
     {
         super(parent, "distributor");
         this.parent = parent;
@@ -125,6 +128,7 @@ public class DistributorCluster extends AbstractConfigProducer<Distributor> impl
         this.hasIndexedDocumentType = hasIndexedDocumentType;
         this.useThreePhaseUpdates = useThreePhaseUpdates;
         this.maxActivationInhibitedOutOfSyncGroups = maxActivationInhibitedOutOfSyncGroups;
+        this.numDistributorStripes = numDistributorStripes;
     }
 
     @Override
@@ -138,6 +142,7 @@ public class DistributorCluster extends AbstractConfigProducer<Distributor> impl
         builder.disable_bucket_activation(hasIndexedDocumentType == false);
         builder.enable_metadata_only_fetch_phase_for_inconsistent_updates(useThreePhaseUpdates);
         builder.max_activation_inhibited_out_of_sync_groups(maxActivationInhibitedOutOfSyncGroups);
+        builder.num_distributor_stripes(numDistributorStripes);
 
         bucketSplitting.getConfig(builder);
     }
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/content/ContentClusterTest.java b/config-model/src/test/java/com/yahoo/vespa/model/content/ContentClusterTest.java
index 811e789752e..677eccfde78 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/content/ContentClusterTest.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/content/ContentClusterTest.java
@@ -1041,14 +1041,19 @@ public class ContentClusterTest extends ContentBaseTest {
         assertZookeeperServerImplementation("com.yahoo.vespa.zookeeper.VespaZooKeeperAdminImpl");
     }
 
-    private int resolveMaxInhibitedGroupsConfigWithFeatureFlag(int maxGroups) {
-        VespaModel model = createEnd2EndOneNode(new TestProperties().maxActivationInhibitedOutOfSyncGroups(maxGroups));
+    private StorDistributormanagerConfig resolveStorDistributormanagerConfig(TestProperties props) {
+        VespaModel model = createEnd2EndOneNode(props);
 
         ContentCluster cc = model.getContentClusters().get("storage");
         var builder = new StorDistributormanagerConfig.Builder();
         cc.getDistributorNodes().getConfig(builder);
 
-        return (new StorDistributormanagerConfig(builder)).max_activation_inhibited_out_of_sync_groups();
+        return (new StorDistributormanagerConfig(builder));
+    }
+
+    private int resolveMaxInhibitedGroupsConfigWithFeatureFlag(int maxGroups) {
+        var cfg = resolveStorDistributormanagerConfig(new TestProperties().maxActivationInhibitedOutOfSyncGroups(maxGroups));
+        return cfg.max_activation_inhibited_out_of_sync_groups();
     }
 
     @Test
@@ -1057,6 +1062,22 @@ public class ContentClusterTest extends ContentBaseTest {
         assertEquals(2, resolveMaxInhibitedGroupsConfigWithFeatureFlag(2));
     }
 
+    private int resolveNumDistributorStripesConfigWithFeatureFlag(TestProperties props) {
+        var cfg = resolveStorDistributormanagerConfig(props);
+        return cfg.num_distributor_stripes();
+    }
+
+    private int resolveNumDistributorStripesConfigWithFeatureFlag(int numStripes) {
+        return resolveNumDistributorStripesConfigWithFeatureFlag(new TestProperties().setNumDistributorStripes(numStripes));
+    }
+
+    @Test
+    public void num_distributor_stripes_config_controlled_by_properties() {
+        assertEquals(0, resolveNumDistributorStripesConfigWithFeatureFlag(new TestProperties()));
+        assertEquals(0, resolveNumDistributorStripesConfigWithFeatureFlag(0));
+        assertEquals(1, resolveNumDistributorStripesConfigWithFeatureFlag(1));
+    }
+
     @Test
     public void testDedicatedClusterControllers() {
         VespaModel noContentModel = createEnd2EndOneNode(new TestProperties().setHostedVespa(true)
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
index 6569bde612a..34220b64808 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
@@ -180,6 +180,7 @@ public class ModelContextImpl implements ModelContext {
         private final ToIntFunction<ClusterSpec.Type> jvmOmitStackTraceInFastThrow;
         private final boolean enableJdiscHttp2;
         private final boolean enableCustomAclMapping;
+        private final int numDistributorStripes;
 
         public FeatureFlags(FlagSource source, ApplicationId appId) {
             this.dedicatedClusterControllerFlavor = parseDedicatedClusterControllerFlavor(flagValue(source, appId, Flags.DEDICATED_CLUSTER_CONTROLLER_FLAVOR));
@@ -206,6 +207,7 @@ public class ModelContextImpl implements ModelContext {
             this.jvmOmitStackTraceInFastThrow = type -> flagValueAsInt(source, appId, type, PermanentFlags.JVM_OMIT_STACK_TRACE_IN_FAST_THROW);
             this.enableJdiscHttp2 = flagValue(source, appId, Flags.ENABLE_JDISC_HTTP2);
             this.enableCustomAclMapping = flagValue(source, appId, Flags.ENABLE_CUSTOM_ACL_MAPPING);
+            this.numDistributorStripes = flagValue(source, appId, Flags.NUM_DISTRIBUTOR_STRIPES);
         }
 
         @Override public Optional<NodeResources> dedicatedClusterControllerFlavor() { return Optional.ofNullable(dedicatedClusterControllerFlavor); }
@@ -234,6 +236,7 @@ public class ModelContextImpl implements ModelContext {
         }
         @Override public boolean enableJdiscHttp2() { return enableJdiscHttp2; }
         @Override public boolean enableCustomAclMapping() { return enableCustomAclMapping; }
+        @Override public int numDistributorStripes() { return numDistributorStripes; }
 
         private static <V> V flagValue(FlagSource source, ApplicationId appId, UnboundFlag<? extends V, ?, ?> flag) {
             return flag.bindTo(source)
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
index 9ce2c6171a6..b3f7f42e308 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
@@ -287,6 +287,13 @@ public class Flags {
             "Takes effect on next host-admin tick",
             HOSTNAME);
 
+    public static final UnboundIntFlag NUM_DISTRIBUTOR_STRIPES = defineIntFlag(
+            "num-distributor-stripes", 0,
+            List.of("geirst", "vekterli"), "2021-04-20", "2021-07-01",
+            "Specifies the number of stripes used by the distributor. When 0, legacy single stripe behavior is used.",
+            "Takes effect after distributor restart",
+            ZONE_ID, APPLICATION_ID);
+
     /** WARNING: public for testing: All flags should be defined in {@link Flags}. */
     public static UnboundBooleanFlag defineFeatureFlag(String flagId, boolean defaultValue, List<String> owners,
                                                        String createdAt, String expiresAt, String description,
diff --git a/storage/src/vespa/storage/config/stor-distributormanager.def b/storage/src/vespa/storage/config/stor-distributormanager.def
index d1c4f35e929..887761ab3b5 100644
--- a/storage/src/vespa/storage/config/stor-distributormanager.def
+++ b/storage/src/vespa/storage/config/stor-distributormanager.def
@@ -273,3 +273,7 @@ prioritize_global_bucket_merges bool default=true
 ## Note: this feature only kicks in if the number of groups in the cluster is greater
 ## than 1.
 max_activation_inhibited_out_of_sync_groups int default=0
+
+## TODO STRIPE document
+## If 0, legacy single stripe behavior is used. Currently supports 0 or 1.
+num_distributor_stripes int default=0 restart