Remove "Push back excessive requests for stats (#83832)"

docs/reference/cluster/nodes-stats.asciidoc

@@ -91,10 +91,6 @@ using metrics.
   `transport`::
       Transport statistics about sent and received bytes in cluster
       communication.
-
-  `stats_requests`::
-      Statistics about stats requests such as indices stats, nodes stats,
-      recovery stats etc.
 --
 
 `<index_metric>`::
@@ -2647,37 +2643,6 @@ search requests on the keyed node.
 The rank of this node; used for shard selection when routing search
 requests.
 ======
-======
-
-[[cluster-nodes-stats-api-response-body-stats-requests]]
-`stats_requests`::
-(object)
-Contains statistics about the stats requests the node has received.
-+
-.Properties of `stats_requests`
-[%collapsible%open]
-======
-`<stats_requests_name>`::
-(object)
-Contains statistics about a specific type of a stats request the node has received.
-+
-.Properties of `<stats_requests_name>`
-[%collapsible%open]
-=======
-`current`::
-(integer)
-Number of stats requests currently in progress.
-
-`completed`::
-(integer)
-Number of stats requests that have been completed by the node (successfully or
-not).
-
-`rejected`::
-(integer)
-Number of stats requests that were rejected by the node because it had reached
-the limit of concurrent stats requests (`node.stats.max_concurrent_requests`).
-=======
 =====
 ====
 

docs/reference/modules/cluster/misc.asciidoc

@@ -101,24 +101,6 @@ number of shards for each node, use the
 setting.
 --
 
-[[stats-requests-limit]]
-===== Stats request limit
-
-A stats request might require information from all nodes to be aggregated before it returns to the user.
-These requests can be heavy and they put extra pressure on the coordinating node (the node collecting the
-responses from all the nodes), for this reason there is a limit on the concurrent requests that a node can coordinate.
-
---
-
-[[node-stats-max-concurrent-requests]]
-`node.stats.max_concurrent_requests`::
-+
---
-(<<dynamic-cluster-setting,Dynamic>>)
-Limits the stats requests a coordinating node can concurrently handle. Defaults to `100`.
-
-
-
 [[user-defined-data]]
 ===== User-defined cluster metadata
 

server/src/internalClusterTest/java/org/elasticsearch/indices/stats/IndexStatsIT.java

@@ -79,7 +79,6 @@
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 
-import static org.elasticsearch.action.support.StatsRequestLimiter.MAX_CONCURRENT_STATS_REQUESTS_PER_NODE;
 import static org.elasticsearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_REPLICAS;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAllSuccessful;
@@ -1387,57 +1386,52 @@ public void testConcurrentIndexingAndStatsRequests() throws BrokenBarrierExcepti
         }
 
         // start threads that will get stats concurrently with indexing
-        try {
-            updateClusterSettings(Settings.builder().put(MAX_CONCURRENT_STATS_REQUESTS_PER_NODE.getKey(), numberOfStatsThreads + 1));
-            for (int i = 0; i < numberOfStatsThreads; i++) {
-                final Thread thread = new Thread(() -> {
+        for (int i = 0; i < numberOfStatsThreads; i++) {
+            final Thread thread = new Thread(() -> {
+                try {
+                    barrier.await();
+                } catch (final BrokenBarrierException | InterruptedException e) {
+                    failed.set(true);
+                    executionFailures.get().add(e);
+                    latch.countDown();
+                }
+                final IndicesStatsRequest request = new IndicesStatsRequest();
+                request.all();
+                request.indices(new String[0]);
+                while (stop.get() == false) {
                     try {
-                        barrier.await();
-                    } catch (final BrokenBarrierException | InterruptedException e) {
-                        failed.set(true);
-                        executionFailures.get().add(e);
-                        latch.countDown();
-                    }
-                    final IndicesStatsRequest request = new IndicesStatsRequest();
-                    request.all();
-                    request.indices(new String[0]);
-                    while (stop.get() == false) {
-                        try {
-                            final IndicesStatsResponse response = client().admin().indices().stats(request).get();
-                            if (response.getFailedShards() > 0) {
-                                failed.set(true);
-                                shardFailures.get().addAll(Arrays.asList(response.getShardFailures()));
-                                latch.countDown();
-                            }
-                        } catch (final ExecutionException | InterruptedException e) {
+                        final IndicesStatsResponse response = client().admin().indices().stats(request).get();
+                        if (response.getFailedShards() > 0) {
                             failed.set(true);
-                            executionFailures.get().add(e);
+                            shardFailures.get().addAll(Arrays.asList(response.getShardFailures()));
                             latch.countDown();
                         }
+                    } catch (final ExecutionException | InterruptedException e) {
+                        failed.set(true);
+                        executionFailures.get().add(e);
+                        latch.countDown();
                     }
-                });
-                thread.setName("stats-" + i);
-                threads.add(thread);
-                thread.start();
-            }
-
-            // release the hounds
-            barrier.await();
+                }
+            });
+            thread.setName("stats-" + i);
+            threads.add(thread);
+            thread.start();
+        }
 
-            // wait for a failure, or for fifteen seconds to elapse
-            latch.await(15, TimeUnit.SECONDS);
+        // release the hounds
+        barrier.await();
 
-            // stop all threads and wait for them to complete
-            stop.set(true);
-            for (final Thread thread : threads) {
-                thread.join();
-            }
+        // wait for a failure, or for fifteen seconds to elapse
+        latch.await(15, TimeUnit.SECONDS);
 
-            assertThat(shardFailures.get(), emptyCollectionOf(DefaultShardOperationFailedException.class));
-            assertThat(executionFailures.get(), emptyCollectionOf(Exception.class));
-        } finally {
-            updateClusterSettings(Settings.builder().putNull(MAX_CONCURRENT_STATS_REQUESTS_PER_NODE.getKey()));
+        // stop all threads and wait for them to complete
+        stop.set(true);
+        for (final Thread thread : threads) {
+            thread.join();
         }
+
+        assertThat(shardFailures.get(), emptyCollectionOf(DefaultShardOperationFailedException.class));
+        assertThat(executionFailures.get(), emptyCollectionOf(Exception.class));
     }
 
     /**

server/src/main/java/org/elasticsearch/action/admin/cluster/node/info/TransportNodesInfoAction.java

@@ -8,10 +8,8 @@
 
 package org.elasticsearch.action.admin.cluster.node.info;
 
-import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.FailedNodeException;
 import org.elasticsearch.action.support.ActionFilters;
-import org.elasticsearch.action.support.StatsRequestLimiter;
 import org.elasticsearch.action.support.nodes.TransportNodesAction;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.cluster.service.ClusterService;
@@ -35,16 +33,14 @@ public class TransportNodesInfoAction extends TransportNodesAction<
     NodeInfo> {
 
     private final NodeService nodeService;
-    private final StatsRequestLimiter statsRequestLimiter;
 
     @Inject
     public TransportNodesInfoAction(
         ThreadPool threadPool,
         ClusterService clusterService,
         TransportService transportService,
         NodeService nodeService,
-        ActionFilters actionFilters,
-        StatsRequestLimiter statsRequestLimiter
+        ActionFilters actionFilters
     ) {
         super(
             NodesInfoAction.NAME,
@@ -58,7 +54,6 @@ public TransportNodesInfoAction(
             NodeInfo.class
         );
         this.nodeService = nodeService;
-        this.statsRequestLimiter = statsRequestLimiter;
     }
 
     @Override
@@ -99,11 +94,6 @@ protected NodeInfo nodeOperation(NodeInfoRequest nodeRequest, Task task) {
         );
     }
 
-    @Override
-    protected void doExecute(Task task, NodesInfoRequest request, ActionListener<NodesInfoResponse> listener) {
-        statsRequestLimiter.tryToExecute(task, request, listener, super::doExecute);
-    }
-
     public static class NodeInfoRequest extends TransportRequest {
 
         NodesInfoRequest request;

server/src/main/java/org/elasticsearch/action/admin/cluster/node/stats/NodeStats.java

@@ -8,8 +8,6 @@
 
 package org.elasticsearch.action.admin.cluster.node.stats;
 
-import org.elasticsearch.Version;
-import org.elasticsearch.action.support.StatsRequestStats;
 import org.elasticsearch.action.support.nodes.BaseNodeResponse;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.cluster.node.DiscoveryNodeRole;
@@ -89,9 +87,6 @@ public class NodeStats extends BaseNodeResponse implements ToXContentFragment {
     @Nullable
     private IndexingPressureStats indexingPressureStats;
 
-    @Nullable
-    private StatsRequestStats statsRequestStats;
-
     public NodeStats(StreamInput in) throws IOException {
         super(in);
         timestamp = in.readVLong();
@@ -112,9 +107,6 @@ public NodeStats(StreamInput in) throws IOException {
         ingestStats = in.readOptionalWriteable(IngestStats::new);
         adaptiveSelectionStats = in.readOptionalWriteable(AdaptiveSelectionStats::new);
         indexingPressureStats = in.readOptionalWriteable(IndexingPressureStats::new);
-        if (in.getVersion().onOrAfter(Version.V_8_3_0)) {
-            statsRequestStats = in.readOptionalWriteable(StatsRequestStats::new);
-        }
     }
 
     public NodeStats(
@@ -134,8 +126,7 @@ public NodeStats(
         @Nullable IngestStats ingestStats,
         @Nullable AdaptiveSelectionStats adaptiveSelectionStats,
         @Nullable ScriptCacheStats scriptCacheStats,
-        @Nullable IndexingPressureStats indexingPressureStats,
-        @Nullable StatsRequestStats statsRequestStats
+        @Nullable IndexingPressureStats indexingPressureStats
     ) {
         super(node);
         this.timestamp = timestamp;
@@ -154,7 +145,6 @@ public NodeStats(
         this.adaptiveSelectionStats = adaptiveSelectionStats;
         this.scriptCacheStats = scriptCacheStats;
         this.indexingPressureStats = indexingPressureStats;
-        this.statsRequestStats = statsRequestStats;
     }
 
     public long getTimestamp() {
@@ -259,11 +249,6 @@ public IndexingPressureStats getIndexingPressureStats() {
         return indexingPressureStats;
     }
 
-    @Nullable
-    public StatsRequestStats getStatsRequestStats() {
-        return statsRequestStats;
-    }
-
     @Override
     public void writeTo(StreamOutput out) throws IOException {
         super.writeTo(out);
@@ -287,9 +272,6 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeOptionalWriteable(ingestStats);
         out.writeOptionalWriteable(adaptiveSelectionStats);
         out.writeOptionalWriteable(indexingPressureStats);
-        if (out.getVersion().onOrAfter(Version.V_8_3_0)) {
-            out.writeOptionalWriteable(statsRequestStats);
-        }
     }
 
     @Override
@@ -359,9 +341,6 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         if (getIndexingPressureStats() != null) {
             getIndexingPressureStats().toXContent(builder, params);
         }
-        if (getStatsRequestStats() != null) {
-            getStatsRequestStats().toXContent(builder, params);
-        }
         return builder;
     }
 }

server/src/main/java/org/elasticsearch/action/admin/cluster/node/stats/NodesStatsRequest.java

@@ -189,8 +189,7 @@ public enum Metric {
         INGEST("ingest"),
         ADAPTIVE_SELECTION("adaptive_selection"),
         SCRIPT_CACHE("script_cache"),
-        INDEXING_PRESSURE("indexing_pressure"),
-        STATS_REQUESTS("stats_requests"),;
+        INDEXING_PRESSURE("indexing_pressure"),;
 
         private String metricName;
 

server/src/main/java/org/elasticsearch/action/admin/cluster/node/stats/TransportNodesStatsAction.java

@@ -8,10 +8,8 @@
 
 package org.elasticsearch.action.admin.cluster.node.stats;
 
-import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.FailedNodeException;
 import org.elasticsearch.action.support.ActionFilters;
-import org.elasticsearch.action.support.StatsRequestLimiter;
 import org.elasticsearch.action.support.nodes.TransportNodesAction;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.cluster.service.ClusterService;
@@ -38,16 +36,14 @@ public class TransportNodesStatsAction extends TransportNodesAction<
     NodeStats> {
 
     private final NodeService nodeService;
-    private final StatsRequestLimiter statsRequestLimiter;
 
     @Inject
     public TransportNodesStatsAction(
         ThreadPool threadPool,
         ClusterService clusterService,
         TransportService transportService,
         NodeService nodeService,
-        ActionFilters actionFilters,
-        StatsRequestLimiter statsRequestLimiter
+        ActionFilters actionFilters
     ) {
         super(
             NodesStatsAction.NAME,
@@ -61,7 +57,6 @@ public TransportNodesStatsAction(
             NodeStats.class
         );
         this.nodeService = nodeService;
-        this.statsRequestLimiter = statsRequestLimiter;
     }
 
     @Override
@@ -100,16 +95,10 @@ protected NodeStats nodeOperation(NodeStatsRequest nodeStatsRequest, Task task)
             NodesStatsRequest.Metric.INGEST.containedIn(metrics),
             NodesStatsRequest.Metric.ADAPTIVE_SELECTION.containedIn(metrics),
             NodesStatsRequest.Metric.SCRIPT_CACHE.containedIn(metrics),
-            NodesStatsRequest.Metric.INDEXING_PRESSURE.containedIn(metrics),
-            NodesStatsRequest.Metric.STATS_REQUESTS.containedIn(metrics)
+            NodesStatsRequest.Metric.INDEXING_PRESSURE.containedIn(metrics)
         );
     }
 
-    @Override
-    protected void doExecute(Task task, NodesStatsRequest request, ActionListener<NodesStatsResponse> listener) {
-        statsRequestLimiter.tryToExecute(task, request, listener, super::doExecute);
-    }
-
     public static class NodeStatsRequest extends TransportRequest {
 
         NodesStatsRequest request;