Merge pull request #28794 from vespa-engine/bjorncs/container-threadpool-configuration

Add feature flag to override search handler threadpool size

5 files changed, 18 insertions, 4 deletions

diff --git a/config-model-api/abi-spec.json b/config-model-api/abi-spec.json
index 2c5be906633..b28401f1873 100644
--- a/config-model-api/abi-spec.json
+++ b/config-model-api/abi-spec.json
@@ -1289,7 +1289,8 @@
       "public boolean useReconfigurableDispatcher()",
       "public int contentLayerMetadataFeatureLevel()",
       "public boolean dynamicHeapSize()",
-      "public java.lang.String unknownConfigDefinition()"
+      "public java.lang.String unknownConfigDefinition()",
+      "public int searchHandlerThreadpool()"
     ],
     "fields" : [ ]
   },
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 57d013ebd01..024a4c233e5 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
@@ -120,6 +120,7 @@ public interface ModelContext {
         @ModelFeatureFlag(owners = {"vekterli"}) default int contentLayerMetadataFeatureLevel() { return 0; }
         @ModelFeatureFlag(owners = {"bjorncs"}) default boolean dynamicHeapSize() { return false; }
         @ModelFeatureFlag(owners = {"hmusum"}) default String unknownConfigDefinition() { return "log"; }
+        @ModelFeatureFlag(owners = {"hmusum"}) default int searchHandlerThreadpool() { return 2; }
     }
 
     /** 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/vespa/model/container/xml/SearchHandler.java b/config-model/src/main/java/com/yahoo/vespa/model/container/xml/SearchHandler.java
index 3cd296c1469..7bdd2ce51a4 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/container/xml/SearchHandler.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/container/xml/SearchHandler.java
@@ -49,16 +49,19 @@ class SearchHandler extends ProcessingHandler<SearchChains> {
 
     private static class Threadpool extends ContainerThreadpool {
 
+        private final int threads;
+
         Threadpool(DeployState ds, Element options) {
             super(ds, "search-handler", options);
+            threads = ds.featureFlags().searchHandlerThreadpool();
         }
 
         @Override
         public void setDefaultConfigValues(ContainerThreadpoolConfig.Builder builder) {
             builder.maxThreadExecutionTimeSeconds(190)
                     .keepAliveTime(5.0)
-                    .maxThreads(-2)
-                    .minThreads(-2)
+                    .maxThreads(-threads)
+                    .minThreads(-threads)
                     .queueSize(-40);
         }
 
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 96b0b03c832..029158056b8 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
@@ -29,7 +29,6 @@ import com.yahoo.config.provision.Zone;
 import com.yahoo.container.jdisc.secretstore.SecretStore;
 import com.yahoo.vespa.config.server.tenant.SecretStoreExternalIdRetriever;
 import com.yahoo.vespa.flags.FetchVector;
-import com.yahoo.vespa.flags.Flag;
 import com.yahoo.vespa.flags.FlagSource;
 import com.yahoo.vespa.flags.Flags;
 import com.yahoo.vespa.flags.PermanentFlags;
@@ -210,6 +209,7 @@ public class ModelContextImpl implements ModelContext {
         private final int contentLayerMetadataFeatureLevel;
         private final boolean dynamicHeapSize;
         private final String unknownConfigDefinition;
+        private final int searchHandlerThreadpool;
 
         public FeatureFlags(FlagSource source, ApplicationId appId, Version version) {
             this.defaultTermwiseLimit = flagValue(source, appId, version, Flags.DEFAULT_TERM_WISE_LIMIT);
@@ -254,6 +254,7 @@ public class ModelContextImpl implements ModelContext {
             this.contentLayerMetadataFeatureLevel = flagValue(source, appId, version, Flags.CONTENT_LAYER_METADATA_FEATURE_LEVEL);
             this.dynamicHeapSize = flagValue(source, appId, version, Flags.DYNAMIC_HEAP_SIZE);
             this.unknownConfigDefinition = flagValue(source, appId, version, Flags.UNKNOWN_CONFIG_DEFINITION);
+            this.searchHandlerThreadpool = flagValue(source, appId, version, Flags.SEARCH_HANDLER_THREADPOOL);
         }
 
         @Override public int heapSizePercentage() { return heapPercentage; }
@@ -306,6 +307,7 @@ public class ModelContextImpl implements ModelContext {
         @Override public int contentLayerMetadataFeatureLevel() { return contentLayerMetadataFeatureLevel; }
         @Override public boolean dynamicHeapSize() { return dynamicHeapSize; }
         @Override public String unknownConfigDefinition() { return unknownConfigDefinition; }
+        @Override public int searchHandlerThreadpool() { return searchHandlerThreadpool; }
 
         private static <V> V flagValue(FlagSource source, ApplicationId appId, Version vespaVersion, 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 0d187514e53..27c9e9ee7da 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
@@ -422,6 +422,13 @@ public class Flags {
             "Takes effect on redeployment through controller",
             INSTANCE_ID, APPLICATION_ID, TENANT_ID);
 
+    public static final UnboundIntFlag SEARCH_HANDLER_THREADPOOL = defineIntFlag(
+            "search-handler-threadpool", 2,
+            List.of("bjorncs", "baldersheim"), "2023-10-01", "2024-01-01",
+            "Adjust search handler threadpool size",
+            "Takes effect at redeployment",
+            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,