CNDB-15155: Segregate SAI's query metrics per query type

src/java/org/apache/cassandra/config/CassandraRelevantProperties.java

@@ -566,6 +566,19 @@ public enum CassandraRelevantProperties
     /** Class used to discover/load the proper SAI index components file for a given sstable. */
     CUSTOM_SAI_INDEX_COMPONENTS_DISCOVERY("cassandra.sai.custom_components_discovery_class"),
 
+    /**
+     * Whether to enable SAI per-table metrics for different kinds of query, such as filter-only queries, top-k-only
+     * queries, hybrid queries, single-partition queries, and multipartition queries. These metrics are always counters.
+     */
+    SAI_QUERY_KIND_PER_TABLE_METRICS_ENABLED("cassandra.sai.metrics.query_kind.per_table.enabled", "true"),
+
+    /**
+     * Whether to enable SAI per-query metrics for different kinds of query, such as filter-only queries, top-k-only
+     * queries, hybrid queries, single-partition queries, and multipartition queries. These metrics are histograms and
+     * timers.
+     */
+    SAI_QUERY_KIND_PER_QUERY_METRICS_ENABLED("cassandra.sai.metrics.query_kind.per_query.enabled", "false"),
+
     /**
      * If true, while creating or altering schema, NetworkTopologyStrategy won't check if the DC exists.
      * This is to remain compatible with older workflows that first change the replication before adding the nodes.

src/java/org/apache/cassandra/db/MultiRangeReadCommand.java

@@ -133,6 +133,12 @@ public static MultiRangeReadCommand create(List<ReadCallback<?, ?>> subrangeHand
                                          command.indexQueryPlan());
     }
 
+    @Override
+    public boolean isSinglePartition()
+    {
+        return dataRanges.size() == 1 && dataRanges.get(0).isSinglePartition();
+    }
+
     /**
      * @return all token ranges to be queried
      */

src/java/org/apache/cassandra/db/PartitionRangeReadCommand.java

@@ -136,6 +136,12 @@ public DataRange dataRange()
         return dataRange;
     }
 
+    @Override
+    public boolean isSinglePartition()
+    {
+        return dataRange.isSinglePartition();
+    }
+
     public ClusteringIndexFilter clusteringIndexFilter(DecoratedKey key)
     {
         return dataRange.clusteringIndexFilter(key);

src/java/org/apache/cassandra/db/ReadCommand.java

@@ -242,12 +242,25 @@ public Index.QueryPlan indexQueryPlan()
         return indexQueryPlan;
     }
 
+    /**
+     * @return {@code true} if this command uses index-based filtering, {@code false} otherwise
+     */
+    public boolean usesIndexFiltering()
+    {
+        return indexQueryPlan != null && indexQueryPlan.usesIndexFiltering();
+    }
+
     @Override
     public boolean isTopK()
     {
         return indexQueryPlan != null && indexQueryPlan.isTopK();
     }
 
+    /**
+     * @return {@code true} if this command only queries a single partition, {@code false} otherwise.
+     */
+    public abstract boolean isSinglePartition();
+
     @VisibleForTesting
     public Index.Searcher indexSearcher()
     {

src/java/org/apache/cassandra/db/SinglePartitionReadCommand.java

@@ -386,6 +386,12 @@ public SinglePartitionReadCommand forPaging(Clustering<?> lastReturned, DataLimi
                       lastReturned == null ? clusteringIndexFilter() : clusteringIndexFilter.forPaging(metadata().comparator, lastReturned, false));
     }
 
+    @Override
+    public boolean isSinglePartition()
+    {
+        return true;
+    }
+
     public PartitionIterator execute(ConsistencyLevel consistency, QueryState queryState, long queryStartNanoTime) throws RequestExecutionException
     {
         if (clusteringIndexFilter.isEmpty(metadata().comparator))

src/java/org/apache/cassandra/index/Index.java

@@ -231,7 +231,7 @@ default IndexBuildingSupport getRecoveryTaskSupport()
     {
         return getBuildTaskSupport();
     }
-    
+
     /**
      * Returns the type of operations supported by the index in case its building has failed and it's needing recovery.
      *
@@ -1101,6 +1101,14 @@ default boolean isTopK()
         {
             return false;
         }
+
+        /**
+         * @return {@code true} if this plan uses index-based filtering, {@code false} otherwise
+         */
+        default boolean usesIndexFiltering()
+        {
+            return true;
+        }
     }
 
     /*