Update default .enabled and exporter.type settings (#217)

Signed-off-by: David Zane <davizane@amazon.com>

Author: dzane17

README.md

@@ -24,13 +24,13 @@ For information about installing plugins, see [Installing plugins](https://opens
 
 ### Enabling top N query monitoring
 
-When you install the `query-insights` plugin, top N query monitoring is disabled by default. To enable top N query monitoring, update the dynamic settings for the desired monitoring types. These settings enable the corresponding collectors and aggregators in the running cluster. For example, to enable monitoring top N queries by latency, update the `search.insights.top_queries.latency.enabled` setting:
+When you install the `query-insights` plugin, top N query monitoring is enabled by default. To disable top N query monitoring, update the dynamic cluster settings for the desired metric types. For example, to disable monitoring top N queries by latency, update the `search.insights.top_queries.latency.enabled` setting:
 
 ```
 PUT _cluster/settings
 {
   "persistent" : {
-    "search.insights.top_queries.latency.enabled" : true
+    "search.insights.top_queries.latency.enabled" : false
   }
 }
 ```

src/main/java/org/opensearch/plugin/insights/settings/QueryInsightsSettings.java

@@ -95,7 +95,7 @@ public class QueryInsightsSettings {
      */
     public static final Setting<Boolean> TOP_N_LATENCY_QUERIES_ENABLED = Setting.boolSetting(
         TOP_N_LATENCY_QUERIES_PREFIX + ".enabled",
-        false,
+        true,
         Setting.Property.Dynamic,
         Setting.Property.NodeScope
     );
@@ -159,7 +159,7 @@ public class QueryInsightsSettings {
      */
     public static final Setting<Boolean> TOP_N_CPU_QUERIES_ENABLED = Setting.boolSetting(
         TOP_N_CPU_QUERIES_PREFIX + ".enabled",
-        false,
+        true,
         Setting.Property.Dynamic,
         Setting.Property.NodeScope
     );
@@ -189,7 +189,7 @@ public class QueryInsightsSettings {
      */
     public static final Setting<Boolean> TOP_N_MEMORY_QUERIES_ENABLED = Setting.boolSetting(
         TOP_N_MEMORY_QUERIES_PREFIX + ".enabled",
-        false,
+        true,
         Setting.Property.Dynamic,
         Setting.Property.NodeScope
     );
@@ -229,7 +229,7 @@ public class QueryInsightsSettings {
     /**
      * Default exporter type of top queries
      */
-    public static final String DEFAULT_TOP_QUERIES_EXPORTER_TYPE = SinkType.NONE.toString();
+    public static final String DEFAULT_TOP_QUERIES_EXPORTER_TYPE = SinkType.LOCAL_INDEX.toString();
     /**
      * Default Top N local indices retention period in days
      */