Forecast write load during rollovers

build-tools-internal/src/main/resources/forbidden/es-all-signatures.txt

@@ -62,3 +62,6 @@ org.apache.logging.log4j.message.ParameterizedMessage#<init>(java.lang.String, j
 org.apache.logging.log4j.message.ParameterizedMessage#<init>(java.lang.String, java.lang.Object[])
 org.apache.logging.log4j.message.ParameterizedMessage#<init>(java.lang.String, java.lang.Object)
 org.apache.logging.log4j.message.ParameterizedMessage#<init>(java.lang.String, java.lang.Object, java.lang.Object)
+
+@defaultMessage Use WriteLoadForecaster#getForecastedWriteLoad instead
+org.elasticsearch.cluster.metadata.IndexMetadata#getForecastedWriteLoad()

docs/changelog/91425.yaml

@@ -0,0 +1,5 @@
+pr: 91425
+summary: Forecast write load during rollovers
+area: Allocation
+type: enhancement
+issues: []

modules/data-streams/src/test/java/org/elasticsearch/datastreams/DataStreamGetWriteIndexTests.java

@@ -27,6 +27,7 @@
 import org.elasticsearch.cluster.metadata.MetadataIndexAliasesService;
 import org.elasticsearch.cluster.metadata.Template;
 import org.elasticsearch.cluster.routing.allocation.AllocationService;
+import org.elasticsearch.cluster.routing.allocation.WriteLoadForecaster;
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.settings.IndexScopedSettings;
 import org.elasticsearch.common.settings.Settings;
@@ -274,7 +275,8 @@ public void setup() throws Exception {
                 testThreadPool,
                 createIndexService,
                 indexAliasesService,
-                EmptySystemIndices.INSTANCE
+                EmptySystemIndices.INSTANCE,
+                WriteLoadForecaster.DEFAULT
             );
         }
 

server/src/main/java/org/elasticsearch/action/admin/indices/rollover/MetadataRolloverService.java

@@ -24,6 +24,7 @@
 import org.elasticsearch.cluster.metadata.MetadataCreateIndexService;
 import org.elasticsearch.cluster.metadata.MetadataIndexAliasesService;
 import org.elasticsearch.cluster.metadata.MetadataIndexTemplateService;
+import org.elasticsearch.cluster.routing.allocation.WriteLoadForecaster;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
@@ -64,18 +65,21 @@ public class MetadataRolloverService {
     private final MetadataCreateIndexService createIndexService;
     private final MetadataIndexAliasesService indexAliasesService;
     private final SystemIndices systemIndices;
+    private final WriteLoadForecaster writeLoadForecaster;
 
     @Inject
     public MetadataRolloverService(
         ThreadPool threadPool,
         MetadataCreateIndexService createIndexService,
         MetadataIndexAliasesService indexAliasesService,
-        SystemIndices systemIndices
+        SystemIndices systemIndices,
+        WriteLoadForecaster writeLoadForecaster
     ) {
         this.threadPool = threadPool;
         this.createIndexService = createIndexService;
         this.indexAliasesService = indexAliasesService;
         this.systemIndices = systemIndices;
+        this.writeLoadForecaster = writeLoadForecaster;
     }
 
     public record RolloverResult(String rolloverIndexName, String sourceIndexName, ClusterState clusterState) {
@@ -296,16 +300,16 @@ private RolloverResult rolloverDataStream(
 
         RolloverInfo rolloverInfo = new RolloverInfo(dataStreamName, metConditions, threadPool.absoluteTimeInMillis());
 
-        newState = ClusterState.builder(newState)
-            .metadata(
-                Metadata.builder(newState.metadata())
-                    .put(
-                        IndexMetadata.builder(newState.metadata().index(originalWriteIndex))
-                            .indexWriteLoad(sourceIndexWriteLoad)
-                            .putRolloverInfo(rolloverInfo)
-                    )
-            )
-            .build();
+        Metadata.Builder metadataBuilder = Metadata.builder(newState.metadata())
+            .put(
+                IndexMetadata.builder(newState.metadata().index(originalWriteIndex))
+                    .indexWriteLoad(sourceIndexWriteLoad)
+                    .putRolloverInfo(rolloverInfo)
+            );
+
+        metadataBuilder = writeLoadForecaster.withWriteLoadForecastForWriteIndex(dataStreamName, metadataBuilder);
+
+        newState = ClusterState.builder(newState).metadata(metadataBuilder).build();
 
         return new RolloverResult(newWriteIndexName, originalWriteIndex.getName(), newState);
     }

server/src/main/java/org/elasticsearch/cluster/ClusterModule.java

@@ -29,6 +29,7 @@
 import org.elasticsearch.cluster.routing.allocation.AllocationService;
 import org.elasticsearch.cluster.routing.allocation.ExistingShardsAllocator;
 import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
+import org.elasticsearch.cluster.routing.allocation.WriteLoadForecaster;
 import org.elasticsearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
 import org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalanceShardsAllocator;
 import org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalanceShardsAllocator.DesiredBalanceReconcilerAction;
@@ -122,7 +123,8 @@ public ClusterModule(
         SnapshotsInfoService snapshotsInfoService,
         ThreadPool threadPool,
         SystemIndices systemIndices,
-        Supplier<RerouteService> rerouteServiceSupplier
+        Supplier<RerouteService> rerouteServiceSupplier,
+        WriteLoadForecaster writeLoadForecaster
     ) {
         this.clusterPlugins = clusterPlugins;
         this.deciderList = createAllocationDeciders(settings, clusterService.getClusterSettings(), clusterPlugins);
@@ -133,7 +135,8 @@ public ClusterModule(
             threadPool,
             clusterPlugins,
             clusterService,
-            this::reconcile
+            this::reconcile,
+            writeLoadForecaster
         );
         this.clusterService = clusterService;
         this.indexNameExpressionResolver = new IndexNameExpressionResolver(threadPool.getThreadContext(), systemIndices);
@@ -344,14 +347,15 @@ private static ShardsAllocator createShardsAllocator(
         ThreadPool threadPool,
         List<ClusterPlugin> clusterPlugins,
         ClusterService clusterService,
-        DesiredBalanceReconcilerAction reconciler
+        DesiredBalanceReconcilerAction reconciler,
+        WriteLoadForecaster writeLoadForecaster
     ) {
         Map<String, Supplier<ShardsAllocator>> allocators = new HashMap<>();
-        allocators.put(BALANCED_ALLOCATOR, () -> new BalancedShardsAllocator(settings, clusterSettings));
+        allocators.put(BALANCED_ALLOCATOR, () -> new BalancedShardsAllocator(settings, clusterSettings, writeLoadForecaster));
         allocators.put(
             DESIRED_BALANCE_ALLOCATOR,
             () -> new DesiredBalanceShardsAllocator(
-                new BalancedShardsAllocator(settings, clusterSettings),
+                new BalancedShardsAllocator(settings, clusterSettings, writeLoadForecaster),
                 threadPool,
                 clusterService,
                 reconciler

server/src/main/java/org/elasticsearch/cluster/metadata/IndexMetadata.java

@@ -69,6 +69,7 @@
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
+import java.util.OptionalDouble;
 import java.util.Set;
 import java.util.function.Function;
 
@@ -523,6 +524,8 @@ public Iterator<Setting<?>> settings() {
     public static final String KEY_PRIMARY_TERMS = "primary_terms";
     public static final String KEY_WRITE_LOAD = "write_load";
 
+    public static final String KEY_WRITE_LOAD_FORECAST = "write_load_forecast";
+
     public static final String INDEX_STATE_FILE_PREFIX = "state-";
 
     static final Version SYSTEM_INDEX_FLAG_ADDED = Version.V_7_10_0;
@@ -608,6 +611,8 @@ public Iterator<Setting<?>> settings() {
     private final Instant timeSeriesEnd;
     @Nullable
     private final IndexWriteLoad writeLoad;
+    @Nullable
+    private final Double writeLoadForecast;
 
     private IndexMetadata(
         final Index index,
@@ -651,7 +656,8 @@ private IndexMetadata(
         @Nullable final Instant timeSeriesStart,
         @Nullable final Instant timeSeriesEnd,
         final Version indexCompatibilityVersion,
-        @Nullable final IndexWriteLoad writeLoad
+        @Nullable final IndexWriteLoad writeLoad,
+        @Nullable final Double writeLoadForecast
     ) {
         this.index = index;
         this.version = version;
@@ -703,6 +709,7 @@ private IndexMetadata(
         this.timeSeriesStart = timeSeriesStart;
         this.timeSeriesEnd = timeSeriesEnd;
         this.writeLoad = writeLoad;
+        this.writeLoadForecast = writeLoadForecast;
         assert numberOfShards * routingFactor == routingNumShards : routingNumShards + " must be a multiple of " + numberOfShards;
     }
 
@@ -752,7 +759,8 @@ IndexMetadata withMappingMetadata(MappingMetadata mapping) {
             this.timeSeriesStart,
             this.timeSeriesEnd,
             this.indexCompatibilityVersion,
-            this.writeLoad
+            this.writeLoad,
+            this.writeLoadForecast
         );
     }
 
@@ -808,7 +816,8 @@ public IndexMetadata withInSyncAllocationIds(int shardId, Set<String> inSyncSet)
             this.timeSeriesStart,
             this.timeSeriesEnd,
             this.indexCompatibilityVersion,
-            this.writeLoad
+            this.writeLoad,
+            this.writeLoadForecast
         );
     }
 
@@ -862,7 +871,8 @@ public IndexMetadata withIncrementedPrimaryTerm(int shardId) {
             this.timeSeriesStart,
             this.timeSeriesEnd,
             this.indexCompatibilityVersion,
-            this.writeLoad
+            this.writeLoad,
+            this.writeLoadForecast
         );
     }
 
@@ -916,7 +926,8 @@ public IndexMetadata withTimestampRange(IndexLongFieldRange timestampRange) {
             this.timeSeriesStart,
             this.timeSeriesEnd,
             this.indexCompatibilityVersion,
-            this.writeLoad
+            this.writeLoad,
+            this.writeLoadForecast
         );
     }
 
@@ -966,7 +977,8 @@ public IndexMetadata withIncrementedVersion() {
             this.timeSeriesStart,
             this.timeSeriesEnd,
             this.indexCompatibilityVersion,
-            this.writeLoad
+            this.writeLoad,
+            this.writeLoadForecast
         );
     }
 
@@ -1162,6 +1174,10 @@ public IndexWriteLoad getWriteLoad() {
         return writeLoad;
     }
 
+    public OptionalDouble getForecastedWriteLoad() {
+        return writeLoadForecast == null ? OptionalDouble.empty() : OptionalDouble.of(writeLoadForecast);
+    }
+
     public static final String INDEX_RESIZE_SOURCE_UUID_KEY = "index.resize.source.uuid";
     public static final String INDEX_RESIZE_SOURCE_NAME_KEY = "index.resize.source.name";
     public static final Setting<String> INDEX_RESIZE_SOURCE_UUID = Setting.simpleString(INDEX_RESIZE_SOURCE_UUID_KEY);
@@ -1397,6 +1413,7 @@ private static class IndexMetadataDiff implements Diff<IndexMetadata> {
         private final boolean isSystem;
         private final IndexLongFieldRange timestampRange;
         private final IndexWriteLoad indexWriteLoad;
+        private final Double indexWriteLoadForecast;
 
         IndexMetadataDiff(IndexMetadata before, IndexMetadata after) {
             index = after.index.getName();
@@ -1431,6 +1448,7 @@ private static class IndexMetadataDiff implements Diff<IndexMetadata> {
             isSystem = after.isSystem;
             timestampRange = after.timestampRange;
             indexWriteLoad = after.writeLoad;
+            indexWriteLoadForecast = after.writeLoadForecast;
         }
 
         private static final DiffableUtils.DiffableValueReader<String, AliasMetadata> ALIAS_METADATA_DIFF_VALUE_READER =
@@ -1483,8 +1501,10 @@ private static class IndexMetadataDiff implements Diff<IndexMetadata> {
             timestampRange = IndexLongFieldRange.readFrom(in);
             if (in.getVersion().onOrAfter(WRITE_LOAD_ADDED)) {
                 indexWriteLoad = in.readOptionalWriteable(IndexWriteLoad::new);
+                indexWriteLoadForecast = in.readOptionalDouble();
             } else {
                 indexWriteLoad = null;
+                indexWriteLoadForecast = null;
             }
         }
 
@@ -1518,6 +1538,7 @@ public void writeTo(StreamOutput out) throws IOException {
             timestampRange.writeTo(out);
             if (out.getVersion().onOrAfter(WRITE_LOAD_ADDED)) {
                 out.writeOptionalWriteable(indexWriteLoad);
+                out.writeOptionalDouble(indexWriteLoadForecast);
             }
         }
 
@@ -1546,6 +1567,7 @@ public IndexMetadata apply(IndexMetadata part) {
             builder.system(isSystem);
             builder.timestampRange(timestampRange);
             builder.indexWriteLoad(indexWriteLoad);
+            builder.indexWriteLoadForecast(indexWriteLoadForecast);
             return builder.build();
         }
     }
@@ -1610,6 +1632,7 @@ public static IndexMetadata readFrom(StreamInput in, @Nullable Function<String,
 
         if (in.getVersion().onOrAfter(WRITE_LOAD_ADDED)) {
             builder.indexWriteLoad(in.readOptionalWriteable(IndexWriteLoad::new));
+            builder.indexWriteLoadForecast(in.readOptionalDouble());
         }
         return builder.build();
     }
@@ -1654,6 +1677,7 @@ public void writeTo(StreamOutput out, boolean mappingsAsHash) throws IOException
         timestampRange.writeTo(out);
         if (out.getVersion().onOrAfter(WRITE_LOAD_ADDED)) {
             out.writeOptionalWriteable(writeLoad);
+            out.writeOptionalDouble(writeLoadForecast);
         }
     }
 
@@ -1702,6 +1726,7 @@ public static class Builder {
         private IndexLongFieldRange timestampRange = IndexLongFieldRange.NO_SHARDS;
         private LifecycleExecutionState lifecycleExecutionState = LifecycleExecutionState.EMPTY_STATE;
         private IndexWriteLoad indexWriteLoad = null;
+        private Double indexWriteLoadForecast = null;
 
         public Builder(String index) {
             this.index = index;
@@ -1731,6 +1756,7 @@ public Builder(IndexMetadata indexMetadata) {
             this.timestampRange = indexMetadata.timestampRange;
             this.lifecycleExecutionState = indexMetadata.lifecycleExecutionState;
             this.indexWriteLoad = indexMetadata.writeLoad;
+            this.indexWriteLoadForecast = indexMetadata.writeLoadForecast;
         }
 
         public Builder index(String index) {
@@ -1950,6 +1976,11 @@ public Builder indexWriteLoad(IndexWriteLoad indexWriteLoad) {
             return this;
         }
 
+        public Builder indexWriteLoadForecast(Double indexWriteLoadForecast) {
+            this.indexWriteLoadForecast = indexWriteLoadForecast;
+            return this;
+        }
+
         public IndexMetadata build() {
             /*
              * We expect that the metadata has been properly built to set the number of shards and the number of replicas, and do not rely
@@ -2128,7 +2159,8 @@ public IndexMetadata build() {
                 isTsdb ? IndexSettings.TIME_SERIES_START_TIME.get(settings) : null,
                 isTsdb ? IndexSettings.TIME_SERIES_END_TIME.get(settings) : null,
                 SETTING_INDEX_VERSION_COMPATIBILITY.get(settings),
-                indexWriteLoad
+                indexWriteLoad,
+                indexWriteLoadForecast
             );
         }
 
@@ -2246,6 +2278,10 @@ public static void toXContent(IndexMetadata indexMetadata, XContentBuilder build
                 builder.endObject();
             }
 
+            if (indexMetadata.writeLoadForecast != null) {
+                builder.field(KEY_WRITE_LOAD_FORECAST, indexMetadata.writeLoadForecast);
+            }
+
             builder.endObject();
         }
 
@@ -2379,6 +2415,7 @@ public static IndexMetadata fromXContent(XContentParser parser, Map<String, Mapp
                             }
                             builder.putMapping(mappingsByHash.get(parser.text()));
                         }
+                        case KEY_WRITE_LOAD_FORECAST -> builder.indexWriteLoadForecast(parser.doubleValue());
                         default -> throw new IllegalArgumentException("Unexpected field [" + currentFieldName + "]");
                     }
                 } else {

server/src/main/java/org/elasticsearch/cluster/routing/allocation/WriteLoadForecaster.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.cluster.routing.allocation;
+
+import org.elasticsearch.cluster.metadata.IndexMetadata;
+import org.elasticsearch.cluster.metadata.Metadata;
+
+import java.util.OptionalDouble;
+
+public interface WriteLoadForecaster {
+    WriteLoadForecaster DEFAULT = new DefaultWriteLoadForecaster();
+
+    Metadata.Builder withWriteLoadForecastForWriteIndex(String dataStreamName, Metadata.Builder metadata);
+
+    OptionalDouble getForecastedWriteLoad(IndexMetadata indexMetadata);
+
+    class DefaultWriteLoadForecaster implements WriteLoadForecaster {
+        @Override
+        public Metadata.Builder withWriteLoadForecastForWriteIndex(String dataStreamName, Metadata.Builder metadata) {
+            return metadata;
+        }
+
+        @Override
+        public OptionalDouble getForecastedWriteLoad(IndexMetadata indexMetadata) {
+            return OptionalDouble.empty();
+        }
+    }
+}