[INFERENCE] Remove node pinning logic

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/InferencePlugin.java

@@ -81,9 +81,6 @@
 import org.elasticsearch.xpack.inference.action.TransportUnifiedCompletionInferenceAction;
 import org.elasticsearch.xpack.inference.action.TransportUpdateInferenceModelAction;
 import org.elasticsearch.xpack.inference.action.filter.ShardBulkInferenceActionFilter;
-import org.elasticsearch.xpack.inference.common.InferenceServiceNodeLocalRateLimitCalculator;
-import org.elasticsearch.xpack.inference.common.InferenceServiceRateLimitCalculator;
-import org.elasticsearch.xpack.inference.common.NoopNodeLocalRateLimitCalculator;
 import org.elasticsearch.xpack.inference.common.Truncator;
 import org.elasticsearch.xpack.inference.external.http.HttpClientManager;
 import org.elasticsearch.xpack.inference.external.http.HttpSettings;
@@ -160,7 +157,6 @@
 
 import static java.util.Collections.singletonList;
 import static org.elasticsearch.xpack.inference.action.filter.ShardBulkInferenceActionFilter.INDICES_INFERENCE_BATCH_SIZE;
-import static org.elasticsearch.xpack.inference.common.InferenceAPIClusterAwareRateLimitingFeature.INFERENCE_API_CLUSTER_AWARE_RATE_LIMITING_FEATURE_FLAG;
 
 public class InferencePlugin extends Plugin
     implements
@@ -382,19 +378,6 @@ public Collection<?> createComponents(PluginServices services) {
             new TransportGetInferenceDiagnosticsAction.ClientManagers(httpClientManager, elasticInferenceServiceHttpClientManager)
         );
         components.add(inferenceStatsBinding);
-
-        // Only add InferenceServiceNodeLocalRateLimitCalculator (which is a ClusterStateListener) for cluster aware rate limiting,
-        // if the rate limiting feature flags are enabled, otherwise provide noop implementation
-        InferenceServiceRateLimitCalculator calculator;
-        if (INFERENCE_API_CLUSTER_AWARE_RATE_LIMITING_FEATURE_FLAG) {
-            calculator = new InferenceServiceNodeLocalRateLimitCalculator(services.clusterService(), serviceRegistry);
-        } else {
-            calculator = new NoopNodeLocalRateLimitCalculator();
-        }
-
-        // Add binding for interface -> implementation
-        components.add(new PluginComponentBinding<>(InferenceServiceRateLimitCalculator.class, calculator));
-
         components.add(
             new InferenceEndpointRegistry(
                 services.clusterService(),

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/action/BaseTransportInferenceAction.java

@@ -16,7 +16,6 @@
 import org.elasticsearch.client.internal.node.NodeClient;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.Randomness;
-import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.util.concurrent.EsExecutors;
 import org.elasticsearch.core.Nullable;
@@ -31,25 +30,19 @@
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.tasks.Task;
 import org.elasticsearch.threadpool.ThreadPool;
-import org.elasticsearch.transport.TransportException;
-import org.elasticsearch.transport.TransportResponseHandler;
 import org.elasticsearch.transport.TransportService;
 import org.elasticsearch.xpack.core.XPackField;
 import org.elasticsearch.xpack.core.inference.action.BaseInferenceActionRequest;
 import org.elasticsearch.xpack.core.inference.action.InferenceAction;
 import org.elasticsearch.xpack.inference.InferencePlugin;
 import org.elasticsearch.xpack.inference.action.task.StreamingTaskManager;
-import org.elasticsearch.xpack.inference.common.InferenceServiceNodeLocalRateLimitCalculator;
-import org.elasticsearch.xpack.inference.common.InferenceServiceRateLimitCalculator;
 import org.elasticsearch.xpack.inference.registry.InferenceEndpointRegistry;
 import org.elasticsearch.xpack.inference.telemetry.InferenceTimer;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Random;
-import java.util.concurrent.Executor;
 import java.util.concurrent.Flow;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
@@ -64,10 +57,6 @@
 
 /**
  * Base class for transport actions that handle inference requests.
- * Works in conjunction with {@link InferenceServiceNodeLocalRateLimitCalculator} to
- * route requests to specific nodes, iff they support "node-local" rate limiting, which is described in detail
- * in {@link InferenceServiceNodeLocalRateLimitCalculator}.
- *
  * @param <Request> The specific type of inference request being handled
  */
 public abstract class BaseTransportInferenceAction<Request extends BaseInferenceActionRequest> extends HandledTransportAction<
@@ -82,7 +71,6 @@ public abstract class BaseTransportInferenceAction<Request extends BaseInference
     private final InferenceServiceRegistry serviceRegistry;
     private final InferenceStats inferenceStats;
     private final StreamingTaskManager streamingTaskManager;
-    private final InferenceServiceRateLimitCalculator inferenceServiceRateLimitCalculator;
     private final NodeClient nodeClient;
     private final ThreadPool threadPool;
     private final TransportService transportService;
@@ -98,7 +86,6 @@ public BaseTransportInferenceAction(
         InferenceStats inferenceStats,
         StreamingTaskManager streamingTaskManager,
         Writeable.Reader<Request> requestReader,
-        InferenceServiceRateLimitCalculator inferenceServiceNodeLocalRateLimitCalculator,
         NodeClient nodeClient,
         ThreadPool threadPool
     ) {
@@ -108,7 +95,6 @@ public BaseTransportInferenceAction(
         this.serviceRegistry = serviceRegistry;
         this.inferenceStats = inferenceStats;
         this.streamingTaskManager = streamingTaskManager;
-        this.inferenceServiceRateLimitCalculator = inferenceServiceNodeLocalRateLimitCalculator;
         this.nodeClient = nodeClient;
         this.threadPool = threadPool;
         this.transportService = transportService;
@@ -161,15 +147,8 @@ protected void doExecute(Task task, Request request, ActionListener<InferenceAct
 
             var service = serviceRegistry.getService(serviceName).get();
             var localNodeId = nodeClient.getLocalNodeId();
-            var routingDecision = determineRouting(serviceName, request, model.getTaskType(), localNodeId);
+            inferOnServiceWithMetrics(model, request, service, timer, localNodeId, listener);
 
-            if (routingDecision.currentNodeShouldHandleRequest()) {
-                inferOnServiceWithMetrics(model, request, service, timer, localNodeId, listener);
-            } else {
-                // Reroute request
-                request.setHasBeenRerouted(true);
-                rerouteRequest(request, listener, routingDecision.targetNode);
-            }
         }, e -> {
             try {
                 inferenceStats.inferenceDuration().record(timer.elapsedMillis(), responseAttributes(e));
@@ -195,73 +174,12 @@ private void validateRequest(Request request, Model model) {
         validationHelper(() -> isInvalidTaskTypeForInferenceEndpoint(request, model), () -> createInvalidTaskTypeException(request, model));
     }
 
-    private NodeRoutingDecision determineRouting(String serviceName, Request request, TaskType modelTaskType, String localNodeId) {
-        // Rerouting not supported or request was already rerouted
-        if (inferenceServiceRateLimitCalculator.isTaskTypeReroutingSupported(serviceName, modelTaskType) == false
-            || request.hasBeenRerouted()) {
-            return NodeRoutingDecision.handleLocally();
-        }
-
-        var rateLimitAssignment = inferenceServiceRateLimitCalculator.getRateLimitAssignment(serviceName, modelTaskType);
-
-        // No assignment yet
-        if (rateLimitAssignment == null) {
-            return NodeRoutingDecision.handleLocally();
-        }
-
-        var responsibleNodes = rateLimitAssignment.responsibleNodes();
-
-        // Empty assignment
-        if (responsibleNodes == null || responsibleNodes.isEmpty()) {
-            return NodeRoutingDecision.handleLocally();
-        }
-
-        var nodeToHandleRequest = responsibleNodes.get(random.nextInt(responsibleNodes.size()));
-
-        // The drawn node is the current node
-        if (nodeToHandleRequest.getId().equals(localNodeId)) {
-            return NodeRoutingDecision.handleLocally();
-        }
-
-        // Reroute request
-        return NodeRoutingDecision.routeTo(nodeToHandleRequest);
-    }
-
     private static void validationHelper(Supplier<Boolean> validationFailure, Supplier<ElasticsearchStatusException> exceptionCreator) {
         if (validationFailure.get()) {
             throw exceptionCreator.get();
         }
     }
 
-    private void rerouteRequest(Request request, ActionListener<InferenceAction.Response> listener, DiscoveryNode nodeToHandleRequest) {
-        transportService.sendRequest(
-            nodeToHandleRequest,
-            InferenceAction.NAME,
-            request,
-            new TransportResponseHandler<InferenceAction.Response>() {
-                @Override
-                public Executor executor() {
-                    return threadPool.executor(InferencePlugin.UTILITY_THREAD_POOL_NAME);
-                }
-
-                @Override
-                public void handleResponse(InferenceAction.Response response) {
-                    listener.onResponse(response);
-                }
-
-                @Override
-                public void handleException(TransportException exp) {
-                    listener.onFailure(exp);
-                }
-
-                @Override
-                public InferenceAction.Response read(StreamInput in) throws IOException {
-                    return new InferenceAction.Response(in);
-                }
-            }
-        );
-    }
-
     private void recordRequestDurationMetrics(Model model, InferenceTimer timer, @Nullable Throwable t) {
         Map<String, Object> metricAttributes = new HashMap<>();
         metricAttributes.putAll(modelAttributes(model));

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/action/TransportInferenceAction.java

@@ -22,7 +22,6 @@
 import org.elasticsearch.transport.TransportService;
 import org.elasticsearch.xpack.core.inference.action.InferenceAction;
 import org.elasticsearch.xpack.inference.action.task.StreamingTaskManager;
-import org.elasticsearch.xpack.inference.common.InferenceServiceRateLimitCalculator;
 import org.elasticsearch.xpack.inference.registry.InferenceEndpointRegistry;
 
 public class TransportInferenceAction extends BaseTransportInferenceAction<InferenceAction.Request> {
@@ -36,7 +35,6 @@ public TransportInferenceAction(
         InferenceServiceRegistry serviceRegistry,
         InferenceStats inferenceStats,
         StreamingTaskManager streamingTaskManager,
-        InferenceServiceRateLimitCalculator inferenceServiceNodeLocalRateLimitCalculator,
         NodeClient nodeClient,
         ThreadPool threadPool
     ) {
@@ -50,7 +48,6 @@ public TransportInferenceAction(
             inferenceStats,
             streamingTaskManager,
             InferenceAction.Request::new,
-            inferenceServiceNodeLocalRateLimitCalculator,
             nodeClient,
             threadPool
         );

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/action/TransportUnifiedCompletionInferenceAction.java

@@ -27,7 +27,6 @@
 import org.elasticsearch.xpack.core.inference.action.UnifiedCompletionAction;
 import org.elasticsearch.xpack.core.inference.results.UnifiedChatCompletionException;
 import org.elasticsearch.xpack.inference.action.task.StreamingTaskManager;
-import org.elasticsearch.xpack.inference.common.InferenceServiceRateLimitCalculator;
 import org.elasticsearch.xpack.inference.registry.InferenceEndpointRegistry;
 
 import java.util.concurrent.Flow;
@@ -43,7 +42,6 @@ public TransportUnifiedCompletionInferenceAction(
         InferenceServiceRegistry serviceRegistry,
         InferenceStats inferenceStats,
         StreamingTaskManager streamingTaskManager,
-        InferenceServiceRateLimitCalculator inferenceServiceNodeLocalRateLimitCalculator,
         NodeClient nodeClient,
         ThreadPool threadPool
     ) {
@@ -57,7 +55,6 @@ public TransportUnifiedCompletionInferenceAction(
             inferenceStats,
             streamingTaskManager,
             UnifiedCompletionAction.Request::new,
-            inferenceServiceNodeLocalRateLimitCalculator,
             nodeClient,
             threadPool
         );